I was discussing this very issue with a couple of buddies of mine.
I brought it to the attention that McDyess is a VERY underrated factor this series. For these reasons...
-This Mavs team is different than in the past. If Spurs elect to go small and use Jefferson on the kraut, then that leaves us more vulnerable in the rebound department. The Mavs have above average rebounding at every position from Kidd at PG, Butler at SG, Marion at SF, Haywood and Damp at C. We don't need to compound that negative aspect by playing small when our wings outside of Jefferson are all undersized. We need to limit the Mavs to one shot per possession as much as possible.
Another point I want to bring up, is something that I quite don't understand. Whenever a team's go to guy gets the whistle as much as Dirk, why do the Spurs choose to go small? Playing a smaller defender on Dirk only makes the defender have to crowd him and play more physical because of the defender being undersized. Which makes it easier for Dirk to create separation by employing his erray of moves from the triple threat position from jab steps and pump fakes, which consequently makes it easier to draw fouls due to the crowding and the quick reflexes necessary to contest.
Wouldn't you rather play a big man like McDyess on Dirk and play the drive( then closing out quick once he picks up his dribble for the jump-shot* This is when Mavs have Dirk iso at the top of the key*)? Me personally I would much rather Dirk take semi-contested 15-20 footers than going to the line 18 times a game.
Same theory when Dirk is on the block or with his back to the basket 5-12 feet out. Why play small? When your going to have to double and often leave the basket and the lane often occupied by your smallest and least threatening defenders? This is when second chance opportunities and cuts to the basket by the opposition from the weak side destroy the Spurs.
Not to mention smaller defenders are going to be more susceptible to fouling Dirk because they are undersized by length and strength. This is another way getting Dirk to the line when Dirk tries to establish his inside game.
McDyess' value is huge this series. IMO