People often view them as a great team because over a 5 year stretch they at least made the conference semi's, once made the finals, and twice had the best record in the league. But when you really break it down, the Cavs consistently took advantage of what the Eastern Conference called playoff teams (2006 WAS 42 Wins, 2007 WAS 41 Wins, 2007 NJ 41 Wins, 2008 WAS 43 Wins, 2009 DET 39 Wins, & 2010 CHI 41 Wins). That is 6 playoff series victories against teams with no more than 43 wins (in other words, non-playoff teams if in the West). Cleveland's ONLY win against a true playoff team was the 2007 Detroit Pistons but even they only won 53 games despite playing in the easier Eastern Conference. That Pistons team would have been a 5th seed in the West so even they weren't really a great playoff team. The 5 times the Cavs went up against a TRUE heavy weight they lost all five series.

I think the Cavs are similar to the Suns in that they are a team that racks up wins in the regular season by feasting on the weaker teams that don't play defense (notice Phoenix only made the list twice despite posting 54+ wins five times in 6 seasons). However in the playoffs against good defenses that are given time to prepare their one-dimensional offenses are somewhat limited and thus they struggle.

I know the East has not been very good, but I would have expected them to do better in this list simply because they played a disproportionately high number of games against 40 win "playoff teams" in the East.

Also, all but 3 of the teams on that list were eliminated from the playoffs by another team on the list (no shame in that) or went on to win the title. The only teams eliminated by a team not on the list was: 2010 Orlando, 2006 Detroit, and 2006 Dallas.
The Orlando team was knocked out by the Boston Celtics who had a dissapointing regular season (against many teams) but turned it on in the playoffs. The two teams from 2006 were both eliminated by the eventual champion Miami Heat who are not on the list.

I'm curious how the talent disparity between the conferences and the relative strength of the lower playoff seeds in each conference impacts things. I'm not too familiar with all of the advanced stats, but my guess is that these studies take into account the strength of each team. Still, it doesn't seem to do us much good to consider how well the 2008 Celtics did against the 37-45 #8 Hawks, especially when the Lakers of that same year had a 50-32 team as the #8 seed. Maybe I'm missing the boat, but I'm curious as to how that might impact things and whether there is a better predictor of success than this study.