As I said in the original post, this has been a question I have used over the years to provoke long conversations in groups of friends, and the answers are often surprising.
The restriction of one jump, to one moment in time, to change a specific event, but still knowing everything you know now, complicates things. You correct a bad decision, but you have unfair knowledge about not just your family and friends' futures, but economy.. (invest in microsoft) ... wars to come, etc.
I think about each change I could go back and make...
... the pros and cons... and all the different moments in MY timeline I could choose.
It makes my head hurt.
When you propose the question over coffee or at a small party, there isn't time for them to get too deep. That comes later, after the friends go home. They often end up discussing the question again, among themselves, or the next time we run into one another. "You know that question? I've been thinking, and..."
Sounds like a King story.. but going back and changing your path?
The new path could be short and extremely painful, and remember. The other rule was no takebacks.
In the end, I decided to pass on the jump.