Interesting, when I was a WoW GM our special “GM WoW Client” contained a lot of features that QA would use.

One of these was showing NPC pathing in the form of dots with lines in between. At any time the WoW client would know next 5 or so waypoints of a mob that was idle patrolling.

I guess it’s more efficient to send a batch of waypoints occasionally than one at a time more regularly.

It was a interesting watching boss fights where the pathing would update quite regularly, especially if the tank had just died and it was systematically clobbering everyone else.