In 99% of situations, I think that the tank should set the pace, that's a privilege of the job.
They can use their common sense to decide if we are likely to win some time doing wall to wall.
Are all party members in cut-scene at the start of the dungeon? newbies? What type of DPS/heals are in the party? Is their gear is ok?
As a WHM usually, I don't care either way. If anything, I want the tank to take a firm decision:
Either we take our time and we pull/kill stuff as we go OR we all sprint, wall to wall and I switch to holy machine.
But I hate if we half do it. Like we start DPSing, I place a Asylum, then we move... that is a NO! XD
