An interesting thing happened during my last practice session. I've been thinking about it since, and still can't quite figure out how the heck this worked.
I got a small cut on the little finger of my playing hand. Nothing major, but I had to improvise a bandage out of a piece of a paper towel and some Scotch tape, for lack of anything better, just so I wouldn't get blood on my clothes or racket. What this effectively did was limit the movement of the knuckle closest to the tip of my finger, preventing me from really gripping the handle with it--the best I could do was loosely wrap it around so that the racket didn't go flying out of my hand, but I had to get all of the stability of my grip from my other fingers. At first it felt awkward, as I'm used to having a very balanced grip when playing shakehand.
Then something weird started happening. I was landing chops I wouldn't normally make, off both wings. I consider myself a pretty consistent chopper (enough so that I'm working on transitioning to a classical defense style), but this was plain uncanny. Against a guy who normally gives me a reasonable challenge, I was getting damn near everything back. For some reason, that subtle change in my grip, of not being able to apply much pressure with my little finger, made an enormous difference in my consistency. I don't think it was a fluke, either, as I played for several hours longer and it felt the same against other players.
I'm going to test it (the closest I can to) scientifically the next time I go to practice, by alternating playing my regular way and with a bit of tape wrapped around that knuckle. I'll report back here if it still works the same magic. Perhaps some other people could try it out to see how it affects their game too.