Another reason for me is, in Act 3 the game stries to force you to go to the end content from the start of the act. But what if you're not ready and want to level instead of getting killed in the end battle?
So what i do mostly, is not talk to Gortash until i got most side quests and companion quests done. Then i go to Gortash, then kill Orin and then kill him, and go to the Elderbrain instead.
But i played all difficulties at least once, to see the differences. I noticed that in Tactician, the game is especially penetrating about that pressure. I don't like that act because of this either. I get that time is running out due to the events, but i still play a game to have fun and relax, not for stress. :P
