Just a snippet of Neil Paine's insider article. (That's the rule, right? Snippets of insider articles are okay, just as long as we don't post the whole thing?)
I don't know how Jefferson does it, but he just makes everything worse.Al Jefferson, Utah Jazz
Jefferson has long been a practitioner of the art of empty rebounding numbers. Superficially, his 9.0 rpg average and 17.2 career rebound rate (30th-best in NBA history) might tempt you into thinking he's a premier glass-cleaner, but those numbers belie the underwhelming impact he's traditionally had on his teams' rebounding performances. Last year, researcher Evan Zamir looked at how players impact their teams' rebound rates (over the previous three seasons), accounting for quality of teammates and opponents. The stats show that for all of Jefferson's individual rebounding stats, he's made his teams softer on the glass on both ends of the floor. That trend has continued in 2012-13; Jefferson still has a major difference between his rebounding rate and that of his teammates, the Jazz aren't rebounding anywhere near as well as you'd predict given their component players, and Utah rebounds much, much worse with Jefferson in the game.
Rebounding is undoubtedly a valuable skill for a player to have, but only if it improves his team's bottom line. All too often, players who put up monster individual rebounding numbers aren't actually increasing their teams' rebound rates.
Other names mentioned in the article include Asik, Hickson, Cousins, and Howard.