Darin's got it. Lemme see if I can explain what I have in mind at this stage:
1. Girth hitch webbing to limb, clip the top (ball lock) 'biner to webbing.
2. Spliced blaze gets clipped to bottom (screw locker) biner
3. Blaze comes down to climber, through a pulley on the harness, back up to the top pulley, through it then back down to the climber.
4. With a split tail, tie a blakes hitch to that last tail of rope.
This allows a weak, overweight, elderly (etc) climber to climb along their normal-strengthed friends.
I've tried both the hitch climber and Mickey mouse up top. They work, but the rope crosses over itself in this setup. When the climber gets up to the top the blakes occasionally gets jammed up under the cross and causes problem for the descent.
love
nick