Why even bring Extreme mode in when you cannot reliably know what is going to happen there? Spirit Within and Circle of Scorn is strong because they get free Potency without triggering a GCD and if used on CD it will have an impact towards your DPS.

IF the MT was holding threat using Shield Oath and I'm chasing up threat via Sword Oath, wouldn't it be logically natural that I can do what he does? Ending Berserk early actually hurts your DPS more than anything, hence why it is only used when you can benefit from the 1 Wrath it generates and use its duration to the fullest. Berserking just for certain burst phases is irrelevant if your DPS can handle it and you are better served with using Berserk on CD unless you know you won't have uptime coming soon.