Look, Mavs fans, I've got nothing against Nowitzki. I've been more than fair about his place in the game. I said earlier in the season he should be starting in the All-Star game, I've called him a no brainer future Hall-of-Famer and a top ten player of the past decade.
I'm just not going to pretend he's not without a boatload of flaws as a player, just because he scores lots of points. People nitpick myriad high scoring bigs like Stoudemire, Bosh, Randolph, etc. and even Hall-of-Famers like Robinson, Ewing, Malone, etc., because they are/were defenseless, or soft, or couldn't be the lead player on a championship team, etc. Yet all of that get's overlooked when it comes to Nowitzki, because he's white.
I'd still take Duncan over Nowitzki, because I value defense, shot blocking, rebounding, passing, screen setting, etc. Duncan's also had more of an offensive impact than Nowitzki. If you don't understand how, they you don't understand basketball.