Enhancement 
I just wanted to edit the answer, I gave to my own question and I could not (because I wanted to add something valuable to it!).

Luckily I could un-validate that answer (because I also created the question), edit the post and validate it again.

Possible improvements:
Validated answers can only be edited with a strikethrough or additions would be marked italic or in a slightly different color. It's also possible to un-validate the answer, if it is edited or to mark it with an exclamation mark symbol with an explanation, that the answer has been edited since its validation.
Also you should be able to un-validate your own answer, if you don't feel, that this answers the question thoroughly enough, I think. But that's debatable.


Related ideas:
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