I agree, this thread is funny as hell. It's PVP, when it happened to me , I didn't know what the hell happened, but it was my fault for being out of position. The person doing it exploited the terrain to his/her advantage, and I give them credit for it.
Now, someone could camp and cliff, and that would be detrimental to their team. is that an exploit? No, but unless you roll with a full pre-made then in theory you could get "that guy" on your team. Personally I would ask them to move on, but if they ignore me I wouldn't harass them. Likely the other teams would take care of him anyway sooner or later (or they should!).