[He does not know what to think of Rassilon using his silky voice on him. Founding fathers are sounding a little dirtier than he last remembered so it sort of stalls him up a bit.] Time Travel. We damned ourselves with it. Created a kingdom based upon the risk of terrible paradox. Inviting in all the terrors that exist between the universes. Without time travel, off to ourselves, we could have existed as long as we would prefer.

Not a pretty alternative, but truly the best one. And one that would never be considered. I'm sure you'll find another. However, my existence in that universe has been terminated. I left upon my regeneration. I can't be of more help to you.