I am not sure how big Tora Bora is (village size?).
My question has always been....Why didn't we just nuke the whole area if we knew he was in there ?
We used bunker busters with minimal effect. The most effective ordnance was fuel-air explosions in the cave entrances that degraded the breathing air and propagated lethal concussions. Caves are tough to attack. People are hard to kill externally.
My feelings have been all along that if we want Bin Laden to come out of his hole and expose himself we should treat him as if he was already dead. He'd take the bait.