I don't have a foregone conclusion; I am simply reporting what four full seasons of evidence say: three seasons with Arenas healthy during his prime plus one season with Arenas not playing due to injury right after arguably his best season. I am also suggesting that the 2009 season is not relevant to this discussion, an important distinction because when we remove the "noise" in Neil's sample from those irrelevant games we are able to see that during Arenas' prime his presence/absence had no real effect on the team's record.

You asked about other examples. I have already cited T-Mac as an example of an All-NBA player who had a very significant impact on his team's record. Since Neil is the one who wrote this article and proposed the thesis that Arenas was an elite player the burden of proof is really on him to find examples of elite players who had such little impact on their team's record for an extended period during their prime. The Arenas sample covers four years.

During Arenas' three best healthy seasons with the Wizards the team never won more than 45 games or made it past the second round of the playoffs even though he had at least one All-Star caliber teammate plus a good supporting cast each season. A useful comparison is that Kobe Bryant led the Lakers to 45 wins in 2006 in the tougher Western Conference with no All-Star teammates, with a starting pg (Smush Parker) who never had success anywhere else and soon ended up out of the league and with one of the worst starting centers in the league (Kwame Brown). So, the individual efficiency stats that are being thrown around here say one thing but when we look at the bigger picture we see something else entirely: Arenas had a good supporting cast in a weaker conference but could barely get his team above .500 during his prime--the same team that could play slightly above .500 without him--while an elite player like Bryant was able to carry a very weak team to the playoffs in a stronger conference.

A team's win-loss record is a fact. Individual offensive efficiency, as defined by the stats you are citing, is a theory; someone else could weigh the boxscore numbers differently and come up with a different theory. Also, even if Arenas was as efficient offensively as you believe there is still not an adequate measure of how inefficient he was defensively.

Regardless of what the theory about Arenas' offensive efficiency says, the facts show that Arenas missed virtually the entire 2008 season, the Wizards made no significant changes to their main rotation, Caron Butler missed 24 games and the Wizards still posted roughly the same winning percentage that they did during the previous three seasons. Another aspect of this situation that is worth remembering is that the Wizards' record during this time frame was far more sensitive to Butler missing games than to Arenas missing games. You say that the Wizards might have won 50 games if Arenas had been healthy in 2008 but there is no evidence supporting that contention: he was healthy for the three previous seasons and they did not win 50 games. However, if you look at the Wizards' record with Butler but without Arenas during 2008 it looks like the Wizards might have won 50 games if Butler had been healthier.

Which specific key Wizards' players do you think just entered their prime in the 2008 season? Jamison was 31, Butler was already an All-Star and Arenas' replacement Antonio Daniels was 32. There is a fallacy in believing that the Wizards who showed improvement sans Arenas would have been even better in 2008 if Arenas had played; perhaps these players performed better in 2008 precisely because they were not sharing the court with a shot-happy guard who did not play much defense.

If your thesis is that Arenas had a significant positive impact in the win column during his prime--which would also mean that his absence with no other significant roster changes would have a negative impact in the win column--then you are should look for better evidence to support this thesis. My evaluation of Arenas is that during his prime he was an All-Star caliber player (i.e, one of the top 20 or so players in the league) but he was a high variance offensive threat who was below average defensively and displayed poor leadership qualities on and off of the court. When he did not play the Wizards missed his offensive explosiveness to some degree but ultimately they could live without this by performing better in other areas (playing better defense, being less explosive but more consistent offensively, having better game to game focus and work habits with guys like Butler and Jamison having a bigger voice). My evaluation is based on actually watching what took place when Arenas played and when he didn't play, as opposed to assuming that certain stats are infallible or that a player who is considered fun to watch by some (Neil mentioned that he is a big fan of Arenas) must be having a big impact on winning.

No, WE have not. You have this foregone conclusion, and evidence be damned.
Several Wizards were entering their prime just as Arenas' chronic injuries began. The loss of Arenas negated major improvements among his teammates. With a healthy Arenas, the Wiz almost certainly win 50+ games in '08.

This is of course just an educated guess. You guess that the team would not have been greatly better with Arenas. That's your prerogative, and maybe Arenas is one of those rare all-NBA players who do not add many wins. Would there be any others?

This is not about the relative importance of interior defense versus perimeter defense; as I said, team defense must be played "on a string" and if one player is not on that string then it is impossible for a team to be very effective defensively. Moreover, the central question here is the thesis posed in this article that Gilbert Arenas used to be an elite player. I disagree with that thesis for the reasons that I already explained and I disagree with citing the Wizards' 2009 record as "evidence" that Arenas had a great impact on his team's record because (1) there are many other factors that explain why the 2009 Wizards were not good, (2) there is no evidence that Arenas had a great positive effect on the Wizards' record from 2005-07 and (3) the Wizards survived virtually an entire season without Arenas and posted the same slightly above .500 record that they posted with him during his prime.

It makes sense that "in games the Wizards didn't win, Arenas didn't play well"--but it does not make sense to call a high variance offensive player who was also a poor defensive player an elite player unless there is some strong statistical and/or anecdotal evidence showing that he had an elite level impact. We have established that Arenas did not have a significant impact on his team's record and we have established that the Wizards were quite capable of absorbing the loss of Arenas' individual offensive efficiency. So what reason is there to believe that Arenas was an elite player. Neil made it quite clear why he enjoyed watching Arenas but there is a big difference between being a popular/fun to watch player and being an elite player on the level of Kobe or LeBron.

Offensive production for the Wizards dropped across the board sans Gilbert in the lineup. The only players who "improved" on that end were Haywood and Butler, and Butler went right back to his usual offensive production in 2009 (a season which Gilbert was also out of the lineup). This goes right back to the efficiency/usage model that has been discussed here multiple times. "Bad shot" Gilbert was still taking and converting tough shots that other teammates couldn't do as effectively without him on the floor.

David,

I'm not saying that perimeter defense isn't important, just not AS important as interior defense. You can go back throughout NBA history and see a great big man for pretty much every great defensive team (even the 90s Bulls, with terrific perimeter defenders like MJ and Pippen, had guys like Grant, Cartwright, Rodman, etc. in the paint). The bigs are more valuable to your team defensively, and you'll "miss" them more from your lineup than a perimeter defender.

You're right about Neil using the Wizards record with and without Gilbert as evidence, but he isn't one to emphasize win-loss record with/without players in the lineup. I think he was mainly focusing on the points he made in the following paragraphs as proof of Gilbert's impact. By the way, WOUDLN'T it make sense that in games the Wizards didn't win, Gilbert didn't play well? He carried alot of his team's offense -- the difference between him at his his best and guys like LeBron who are obviously better players is that the teams they played on could at times compensate for subpar games from their stars with their defense. Something that the Wizards were never known for.

If you talk to any good basketball coach, he will tell you that a good defensive team has to be "on a string"--if one player is not on that string, then the whole defense collapses. You are right that it is very important to have good interior defenders but it is also important and valuable to have a guard who either puts pressure on the ballhandler or at least stays in front of him and prevents him from easily getting to the hoop (this depends on whether the coach's philosophy emphasizes pressure or just playing sound, fundamental defense--for instance, Larry Brown's best teams were known for their "jump/switch" defense, while Popovich's Spurs do not go for a lot of traps or steals).

You are right that good NBA defense is not primarily based on one on one confrontations but my point is that Arenas is a bad team defender; he takes gambles and is often out of position and those kinds of things break down a team's defense.

I am not sure what you are asking me to rethink. The author of this post theorized that Arenas was at one time an elite player and the first piece of evidence that the author cited was the Wizards' record with/without Arenas. I pointed out that 2009 should not really "count" as part of Arenas' prime and that during Arenas' prime we have three years in which he played and the team was little better than .500 plus one season in which he missed virtually the entire campaign without the Wizards declining. The body of evidence suggests that those who theorize that Arenas was an elite player have to do the rethinking.

Also, I am not completely convinced that the issue here is as simple as figuring out how much Arenas added offensively versus how much he subtracted defensively. Arenas was a high variance player offensively during his prime, as James' stats pointed out. When Arenas was hot the Wizards had a better chance to win but victory was hardly assured--but when he was cold the Wizards were almost certain to lose. Removing Arenas from the lineup in 2008 probably led to much less variance offensively and that is another reason that the Wizards did not suffer as much in the standings as some might have expected.

Perhaps Gilbert wasn't that much worse than Daniels on the defensive end, but he strongly influenced the entire squad as the "go to guy." As has been mentioned, Arenas is known to take shots not conducive to winning and was an "all or nothing" type player. Daniels, on the other hand, was a drive and get fouled type player who didn't force shots. He would more often than not make the right play. Case in point, Arenas has a career 1.7 assist/turnover ratio, while Daniels is at 3.09. While the overall offensive team rating dropped, the individual performances (as mentioned elsewhere here) of the other players suddenly became "career years" offensively when Arenas missed time.

It widely known that some players are more important to defense in basketball than others. Namely the center and interior defenders - mainly because especially at the pro level, even the best perimeter defenders can be beat off the dribble, and a great defender in the paint can make up for it. These guys ANCHOR their squads defensively. The other important thing to keep in mind is that a staple of a great defense is great help defense. One-on-one confrontations certainly take place, but only within the context of a team defense that is primed and in position to defend wherever the ball is on the floor. Defense in basketball is more team-based than offense is, and the best defenses boast these two qualities.

With all that said, it's hard to believe that Antonio Daniels, a player that started for Gilbert when he was injured, was THAT much better than Gilbert defensively (if he even was at all; he was ALSO a below average defender) he offset the advantages that Gilbert brought to the team offensively, thus enabling the Wizards to maintain a solid record. You're gonna have to rethink that one.

The point is that there is not a valid way to prove exactly what an individual's impact on defense is; this is one of the shortcomings of basketball statistical analysis at this stage.

Chess masters note that one incorrectly placed piece makes the whole position bad and I would argue that an analogy could be made to team defense in basketball: one incorrectly placed player breaks down the whole scheme. Also, as a point guard Arenas served as the first line of defense: when he broke down by allowing dribble penetration and/or leaving his man open this resulted in a chain reaction.

Also, I don't understand why we should believe samples of questionable value (the 2009 Wizards' record, posted two years after Arenas last played at a high level and after he had injuries that likely permanently reduced his abilities), small samples or advanced metrics with questionable predictive value when we have larger, more significant samples that all suggest that even at his best Arenas was not an elite player:

1) We have three seasons when Arenas was healthy and put up his best individual numbers yet could not make the Wizards into anything more than a slightly above .500 team.

2) We have almost a full season that the Wizards played without Arenas right after arguably his best season and the Wizards did not decline despite making no other significant changes to their rotation.

3) We have the stats that James provided, which support my observation about Arenas being a high variance player.

4) We have the example of T-Mac, an All-Star/All-NBA guard who had a much greater impact on his team's record than Arenas did during the mid-2000s.

All of these "data points" indicate that Arenas did not add many wins when he played, that the Wizards did not lose any wins when he was out and that a legit elite player (i.e., T-Mac) does affect his team's record. On the other side, we have individual metrics that indicate that Arenas performed efficiently offensively but these numbers tell us nothing about how this correlates with wins or how much Arenas cost his team defensively--and we have the fact that the Wizards were terrible in 2009, but it could be strongly argued that the absence of Haywood and other factors were more important than Arenas being out that season (particularly since Arenas being out in 2008 had no discernible impact in the standings).

FWIW - and I admit that the sample size is small here - in the games that Gilbert played in 2008, the Wizards were actually pretty good on defense.