Suggestion: Visible edit history of posts / comments

One of the few things I think Facebook does well is that it allows you to edit your posts and comments, but you can click a little thing labeled "This has been edited" and when you do it takes you to the edit history of that comment, showing everything it previously said.

This has been on my mind as I often make comments and realize seconds after posting that I should have said something differently and so I edit the comment I made, but I worry someone might be replying to my comment while I'm editing and their reply might only make sense to the pre-edited version. If I have to walk away from the Internet right after, I'd rather not leave them confused.

It's primary function though is as an insurance policy against potential misuse of the edit feature, as it creates accountability for people who might edit their comments claiming "I never said that!"

I have no idea how hard/easy this feature would be to program in, though, or if it's even possible with whatever website framework is being used for this site. But I think it would be a good idea, and I hope it would be relatively painless to implement.