The problem with tunes in a session is the speed defaults to the comfatable speed of the group unless you have a """" in the session then they try to go fast.The etiquette of a session should be the person starting the tune sets the pace/tempo. there is relivant quote by an accomplshed muscian where he is learning to play tunes slower. Therefore IMHO if you are learning a instrument and a tune and you go into a session you set the tempo. Remember Salmon Tails is played at a high tempo in was written as a slow air.