My Answer:
Answers in comments should be left alone.
To migrate a comment to an answer to a question, does not dictate the answer will be marked as the answer. The ability to "Curate" answers is or should be based on Answers that are marked as THE answer, unless of course one just wants all the answers that SE has regardless of .... well anything.
Putting a comment that is The Answer as an Answer just begs for the Low Quality Answer flag regardless of accuracy. Why because it is demonstrated that people want a 20,000 word dissertation explaining the question OR want to have extensive chats about aspects of the answer etc.
My opinion:
The down/up vote on questions and answers is all to often "low quality to wrong" "votes". Based on my observation in our chat room and others, I can feel quite confident I am not alone in observing this and will go so far as to say there are conversations justifying an action based on Up Votes, Favorites(stars?) and answers triggering some pattern recognition that indicates a VtC.
What this all means is that Humans are driving this community and they can have bad hair days, they can have playful hair days, they can have "insert motivation" hair days. This question is asking about one method of dealing with this, supplying the questioner with the answer they are looking for .... in a pseudo protected mode.
Based on some of the wording in the Question and answers, it comes off as, that the answers in comments are protected, affects people, in a negative / non professional way.
In a different forum, there was a question asked, because I didn't know what the question asked for existed I decided to get an answer for my self. I did, I found the answer and posted a short comment with the link to the answer.
A high rep person, suggested it be made an answer. I felt fairly safe that answering it would not cause problems.
Nope, not at all, within 5 minutes of answering it, 2 or 5 down votes, the question is decided to be a duplicate of another question, which in my opinion took a 100% abstraction of the other question and a 99% abstraction of 1 of 9 answers to a question asking an opinion vs the question I answered asking were is this.
Then in chat come to find out that one person believed the answer I gave, violated the rules of SE while others didn't.
I simply removed the links and substituted the google search.
Regardless, the down votes stay, the question got closed as a duplicate etc.