I'm sure there are folks on here that are far more qualified to answer and with greater technicality, but here's my two cents. As for cooling, based on my experience with having trolling motors apart for repair, the skeg will be negligible at best in the cooling of the motor. As for motors getting hot, I recently heard a couple of cats fighting outside a few nights ago and went out to find cat hair all over my deck and my MotorGuide trolling motor running on high. It had ran for about 8 or 9 hours before I discovered it and determined the cats had managed to flip the switch from momentary to constant. The motor was very hot, but has functioned fine since then. I believe the only difference you will see from cutting the skeg off is steering performance, but I'm not sure how much.