I started with a 5 month old in late Jan. This is about my whole story - and it sounds a bit like yours:

http://www.ball-pythons.net/forums/s...ad.php?t=46468

Also, I mentioned in another thread that I did move to larger prey prior to seeing a slow-down.

Also, I would say as long as he's eating (mine eats right away) handle him daily (aside from post-feed, shed, pre-poo, etc). I think alot of the literature around is geared towards troublesome balls. I'm getting the impression that if your BP is eating well then you don't have much to worry about.