If the person you are attacking stops the attack before you destroy their building, do you get any gold/elixir? If so, do you get more if you made more progress in tearing the place apart before you were stopped?
I'm trying to figure out if there is any reason to put more than one nerd on a building. Obviously putting 10 nerds/building gives you the best chance of actually destroying it. But if they get back and stop you, have you just thrown away 10x as many nerds as you needed to?
I hope that made sense...