In Moderator Tools, when an answer is flagged as "Not an Answer," and a moderator clicks the "Delete Post" link to delete it, a system-generated comment should be added to the answer.
The comment should read:
This is not an answer...See the FAQ for more info. - Community ♦
This should also work in the same way if an answer gathers enough deletion votes from 10K users to be deleted.
Alternatively, clicking on the "Delete Post" link could bring up the following dialog:
Taken from this User Script. The script is good, but it only works on actual displayed posts, which defeats the purpose of the Delete Post link in moderator tools.