I'm curious whether a professor strap affects proper pad size for a goalie who is between sizes. AFAIK, pads are measured with reference to either ATK or FTK and visually by whether the center of the knee aligns with the center of the knee stack.
What a professor strap does is secure the pad below the knee to keep it from sliding down (or up) the leg.
For me, the pad sliding down when going into the butterfly has happened several times. Because the pad slid down on me, my knee would slip off the top of the stack when moving in the butterfly and hit the ice. This happened with my 33+1 CCM pads, my Medium Bauer 1S Od1n pads, and more recently, with my Large Bauer 2S Pro pads.
Would a professor strap prevent this, or is it strictly a sizing issue? I'm asking, because newer Bauer pads (Ultrasonic and Mach) do feature a professor strap, but older ones don't.