Doing the companion questline for the first time now, and am supposed to go with the circle to Ysgramor's Tomb.
Now I realize I could probably make my own way there, but decided to follow the circle making my way there. The pathfinding svcks!
I can't understand why the developers would not hard-code a route for people to take in these sorts of specific quests that involve long-distance travel. The pathfinding algorithms clearly aren't up to the task.
I'm now going around in circles near Dawnstar - my peeps go up one slope quite a long way, then think better of it, double back, and try another way. After a while, they turn back again, and repeat the previous mistake. And so on. They're on their third go-round now.
I think I just have to find my own route there, and hope that the others eventually show up.
Really svcks though.