Letting the stronger players take the early lead is the best way, in my opinion, to set the bar higher so that the weaker players have a standard to strive for. Letting the weaker player take the early lead usually results in the weaker player worrying more about messing the song up for the others and actually stopping to back up and repeat what they missed and totally throwing the idea of maintaining a consistant tempo out the window. The weaker player must get proper tempo technique down first by playing the backup chords for better players before they themselves try to play leads. It may take several times playing behind others in a group before you are ready to take a lead, especially if you do not practice leads between class meetings. You only get better when you play with people that are better than you and you PRACTICE.......