Background: I posed a question on the main site a little over a month ago, asking if something could exist. The answer I was given was that it could not exist, and then a "proof" was given, assuming that it did exist, breaking it up into four cases, and showing that in each case we had a contradiction.
At the time of the initial posting, I didn't see anything off about it. Upon further analysis, I couldn't see how the reasoning flowed in two of them, and asked for clarification about a month back (and I did tag the answerer in the comment), but never heard back. I see the answerer on the site daily, so (unless the notification was never sent) the answerer should have been aware of my request.
Today, I finally got the chance to sit down and seriously think about it, and developed counterexamples for 2 of the 4 claims. The mistakes made were very natural and understandable, but they are mistakes.
My questions for the meta: I could make a brand new question referring to the old one and saying "the given answer is half wrong"...but that just feels rude. Is there a preferred way for me to reach the answerer to discuss this? Should I post an answer to my original question with my counterexamples (they are too long for a comment)?
Edit: Upon request (and because I can't really prevent people from going to my own profile and figuring out which post I'm referring to and who the answerer is), here is the link to the post in question: Conflicting definitions of "continuity" of ordinal-valued functions on the ordinals