I will admit that I don't have ToM before I make this post, but that's simply because I've decided to do other things instead, such as the Sleeper and Sword quests, as well as run the raid (without a chance of reward) to make sure I know the mechanics pretty well before going into HM. That being said, the only really...time related part is waiting from one reset to another for a different boss from T3 CoO. You don't even have to do that if you time it right.