I've played most of my tennis life with Kevlar and in the past few years have played a lot with polys. I've strung up a couple rackets with ToughGut/poly hybrids. What I find is that oftentimes I swing at/hit the ball too hard with the gut strings. I'm used to the kevlar or poly pancaking the ball - crushing the ball in - when I hit it. With gut, it doesn't really do that, it takes the ball, absorbs the ball, and then shoots it back without crushing into the surface of the ball. Of course, this is easier on my arm, which is a major reason I use the gut. The problem is that I am used to the pancaking of the ball and tend to keep swinging harder and harder to induce that feeling at impact. I end up driving the ball at my practice partner so hard he can't return it when really I am only intending to have a nice practice rally. Anyone else tend to swing too hard with the gut strings? How long did it take to get used to it and were you able to switch back and forth from gut mains to poly mains and back successfully?