You move one step closer to your ideal world by having a
do-over. What if Trane hadn't died young, as lamented in the
Ascension node? You get Trane back, but run the risk of losing
Nirvana in this new universe.
What if Kurt Cobain hadn't offed himself? If you get him back, how would you then feel if he cleaned up his life at a Fred Phelps Boot Camp?
What if Gary Kildall had won the PC OS war? Would we then be using cups and string to post here?
One thing I know: you never know.