What exactly were you typing that took so long he got far enough to have enough adds to mulch him? Was it important or relevant to the dungeon/your abilities in the dungeon?

Pulling big probably won't ever change given the way this game works. Now that sprint is free, I like when tanks sprint because we should all sprint and be done with the dungeon sooner.

Sprinting with a pull also means less time in transition and more time keeping aggro while dps go to town.