|I know what you mean, but ...
It's all about communication and conversation: you can be having a relevant conversation with someone who didn't post the original question, just a comment to an answer. Adding a solution doesn't notify them and doesn't help the original poster because he lost interest when his code worked three years ago!
In an ideal world such conversations would be in a separate forum rather than QA, but that's a PITA to work out for humans, never mind code.
Plus, posting multiple answers looks like rep point hunting to some people (and normally is).
Modifying the solution doesn't help that either as you need the Scuba gear to get through that after a short while - and it disconnects the answer from the comment it replies to.
I don't think there is a perfect solution ... Or maybe there is.
Perhaps the answer is to have a way to branch off a new QA question if you are replying to a non-OP comment and it's a long / technical reply? That way, the new poster gets a good reply, and the original question isn't clogged up with "side issues" that aren't necessarily direct related to the original? Not sure of the mechanics - it's not even 06:00 and I haven't had yet.
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
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