Okay, seconded?
I can look through my (usually long) posts and pick up spelling and grammar errors, but I seemingly always find additional problems when the post "goes to print".
Giving a 120 second window before the 'Edited' remark kicks in, would seem to be useful? Even spell-checking doesn't always work, because it can't check for the wrong word used, (ie. they're - their - there) and the grammar checker throws up too many spurious mistakes too.
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