For those not familiar with MMOs, the term "aggro", etc...
Just want to point out, there is a reason that abilities like "Taunt" and the "aggro" mechanic in MMOs does NOT work in PvP ("player vs player" rather than "player vs NPC"). It would not be fun to force one player to attack another player just by clicking a Taunt button. So this mechanic is disabled in MMOs when you are fighting against other players, because there is someone behind the wheel of that player, making the decissions. Versus an AI controlled NPC who can't "think" for themselves.
This also reminds me of the debate for social skills. PC social skills vs. an NPC is a good way to dictate the NPCs actions. Either, if the DM doesn't know how the NPC should act OR if the DM doesn't want the NPC to volunteer info, but wants the PCs to have a chance to get the info from the NPC. That is how I see social skills primarily being used. But PC vs PC or NPC vs PC should not have the same parameters when it comes to social skills. You shouldn't be able to force a PLAYER to act in a certain way just because you rolled really high on your Intimidate skill.