[HighStakesPro]

The problem here is the equivocation of "large" and "small". The stacks you're trying to attack are the ones who have enough chips so that they aren't forced to make a move, but are low enough that they can't put any real pressure on you by threatening to take a lot of your stack. This is of course if you have a large stack. Early in the tournament this isn't really applicable because even if you doubled up, most stacks can still seriously hurt you. Later in the tournament, a big stack might mean 5x or more as much as some of your oponents. That's when you can attack them. They can't put pressure on you so they'll need a hand to play back.