Stupid waypoint tricks!
So I built this mission where I have two friendly wings engaged in "zone defense" escort duties, i.e. a ship comes in and they fly over and escort it until it leaves, then they wait around for another ship to show up they can escort. But I don't want these fools cluttering up my jumpnode and maybe ending up smeared across the front of a TC-TRI, so I give them waypoints where they go to when they're not escorting stuff.
Single waypoints.
I go into the mission to test it and stare, totally confused, utterly baffled, as they proceed to form a ball of colliding fighters. And then suddenly I realize the AI isn't smart enough to orbit a waypoint, it has to get to it, come hell or high water. I assigned whole wings a single waypoint.
"YOU BLOODY IDIOT!"