I consider myself semi lore-savvy on the Elder Scrolls, but I've always been confused by a certain element of Dragon Breaks.

My understanding is that when a Dragon Break occurs, Akatosh (time) is "removed from the equation" in Mundus, allowing for many events to happen at once in non-linear ways, before these events correct themselves (right?).

My question is that why is it that the activation of Numidium removes Akatosh's (again time) influence from Mundus. The Numidium was designed for transcendence by the Dwemer, using the heart of Lorkhan or a Shezzarine. Is it the powering of Shezzar's heart that causes time to stop functioning, given the apparent Akatosh/Lorkhan duality?

Any help would be much appreciated.