I think once someones hash rate reaches a certain threshold 100-200Mh/s they should be required to show some kind of proof that they aren't a bot net. otherwise its almost encouraged to do so. if it is a botnet he's stealing electricity from thousands of people and stealing from the pool as well by hogging all the coins. lol
Who would they show "proof" to? What does H20 care if its a botnet?? They are significantly adding to his bottom line.