I've gone back to gi pants for classes and rolling (well before surgery anyway... grr... mat withdrawl.). Eddie made the comment a long time ago and I re-posted it a while back about gi pants improving your game. Eddie's point was that early in your no-gi jiu jitsu career you're likely to find your half guard getting passed pretty regularly because you haven't developed the squeeze and control. As a result, you don't get many reps with your lockdown, quarter guard, mini stomp, etc. With gi pants you have a lot more friction so you're able to get more reps in at an earlier stage of your development. And we all know it's the reps that improve your game. More quality reps = more improvement. Since the pants prevent your partner from passing immediately, you get the chance to actually work the technique. Plus training in the summer in them is just hot as balls and I like that from a conditioning standpoint.