I imagine if you could control one of the 3 available Elder Scrolls (if they aren't actually the same one at different times - or multiple ones interchanging) / You could set yourself back to before the Emporers assassination, you could blink into that phase of time, prevent the incident, and whole mess would never transpire. But, you have to think, what ripples in time would that cause? Maybe only 1 timeline exists fluidly enough to contimue past a specific "historical" significant event. Its possible, that by changing the events of a timeline, you in effect, destroy its ability to proceed.
When you went back through the rift to get the Dragonrend shout, you didn't affect the events outcome, you witnessed it and carried forward knowledge because of it. Did it affect time? Yes, but from the point you returned - Unless that was the opened lock that prevented time from swallowing up this existance. Afterall, you did send the World Eater back into the rift, and time, did move forward.
Edited by Brandy_123, 29 July 2012 - 04:18 AM.