Adding such lengthy cutscenes to a mandatory dungeon in an MMO is just bad design. It's all well and good to have story in your MMO, but make the intro cutscene happen before queue, add no cutscenes during the instance (unless they're ~a minute, maybe) and have the ending cutscene happen upon exit. SE has gotten much better about this in more recent content but in the case of Castrum Meridianum or Praetorium I'm afraid I have to side with people who say, "Just watch them later."