I have been pretty curious about your defense strategy. I took a quick look at your games and that added to your posts on forums (discussing SB) made me come to a conclusion of your defense. :D
So my guess is that you use 3-2 because you want to minimize opponent's 3-point shots. I assume that your players have great inside defenses and especially very high shot blocking skills. Therefore you trust they can handle opponent's offense even if it they use LI. And, well, it appears to work very well. :)