Instead of being hidden "inside" the original post info and only shown when we mouseover the original post info, I suggest both info could be visible side by side like this example:
Original post: November 01, 2015, 02:12:45 PM - Last edit: November 11, 2015, 02:43:34 PM
Some users get confused trying to figure out if post is old or if it's been updated recently...
I guess that would be a very simple change in the code.
IMO the current implementation is better (though that one is there in beta ). Showing last edit makes it appear more relevant than it is.
I suggest adding a help section specific to bitcointalk.org forum like https://bitcointalk.org/index.php?action=help or even a wiki