Being a bit of a sessionist, I have experienced differences. Generally speaking everyone plays the dance tunes far too quickly. When confronted with a couple of dancers at the session they are forced to play slower, and when that happens you get the feeling that the tunes are being dragged! I know I have been there! Obviously it is a rush to fly through a good reel, but if you asked a good dancer to dance to it at that speed they would not be impressed. So I reckon it does one good to listen to both the virtuosi and the ceilibands, and hit a middle.