meh, knockbacks seem to be a staple. It's when they're overly obnoxious on the player, or, like in EQ2, there was the knock UP that flung entire raids in the air. But that's SOE's failing story.

If an NPC kb's a player, a lot of games give it a stun as well, but even without the stun effect it still disorients the player, even just a little bit. Both you and the mob are running back at each other, you make sure the mob doesn't take aggro and run off on someone else, in the mean time getting completely out of position for the entire group. Depending if the mob has any frontals and if the mages are paying attention, if there's a memwipe on aggro or if there's a stun on the tank with the knockback, it can get really hairy. It sounds annoying, but rather than falling asleep at the keyboard with the same old hack n' slash it can at least keep you awake knowing something could happen at any second.

Again of course assuming the feature is installed correctly. As for the Conji thing, the only thing I saw it for was the "Get the ef away from me, that's my purse!" button, which is more useful than an idiot mage running around the camp to shake aggro, only to pull more mobs.