its not about better. fisrt off, i disagree on Mags being better than Damp. they are = at best. Damp has the D Mags has the O. the Bucks need to strengthen their middle and Damp can do that. plus its been shown that he is ok coming off the bench. also, the Bucks need to get somethign for Mags b/c Ill bet anything he will up and leave them with or without a S&T.
as for Simmons, they trade a guy that didnt mesh that well for another 6th man who is a little better defensively, is a big expirer to make up for losing Mags expiring contract and a guy that gets you FTs.
really i think it helps both teams in the short and long run.