The "don't be a dick rule" is meant to be subjective. We can apply it to any situation we want. Generally speaking, we want to apply it to players that are making people leave the server. If somebody is doing something to cause people to go elsewhere (i.e. griefing, excessive TK'ing), then we are well within our rights to ask the guy to leave with our boot in his ass. But if he's just playing in a fashion that we don't like, and is NOT causing people to leave the server, then I don't see what we're trying to accomplish, aside from giving people ammunition to accuse us of admin abuse.
So to sum up, the "don't be a dick rule" is applied to people that make others leave the server. If the guy in the uncap is doing that, then I think we should 1) ask him to stop, 2) kill or warn him, 3) kick him. ONLY if people are leaving the server because of him.
I would also apply this to base rapers. If you are spawn camping the main base of the other team, and it's causing people to leave, you will be 1) asked to stop, 2) killed/warned, 3) kicked from the server.
We want people to play how they want, but not at the expense of emptying our server.