I don't put the spring pan in water. I just put a pan of water on the rack under the rack that the cheesecake sits on.
I've also found that if I "settle" the pan...you know drop it a little to get bubbles out and what not, sometimes that helps with the cracking too. BUT, in all the years I have been making cheesecake, ONLY ONE has come out without ANY cracks. Most will have just a faint little crack if I put the pan of water in.