If you add this, to honor active gaming:
Then please punish players for AFK-Farming as well. Add something like, if player is not moving and is not using skill #1 for a period of time, player and players pet don't deal damage!
And please add Mechanical Genius to the other pet professions as well, to make it fair. Revenant -> Ghosts, Mesmer -> Illusions, Elementalist -> Elementals, Engineer -> Turrets, Necromancer -> Minions, etc.