ORS, were you ever a pitcher? A fastball requires you to throw a baseball straight. Breaking stuff is all about timing your snap and feel. In the freezing cold, you dont have feel for the ball.
On your other point, Derek Jeter said that stretch was the coldest he has EVER been on a baseball field. In October, it may drop into the 40s overnight. In the night game when it snowed, the temp was in the high 20s with a wind chill near zero.