OK. Since checking all mails in the long thread is tedious job, I will
pick some up and leave a comment in the b.p.o.
Personally, I think that just linking to the python-dev thread in bpo (and/or PR) is adequate for most cases, especially if there was a fairly strong consensus pointing in one direction.
(More detail can be helpful of course, but if one can only spare enough time to just place a link on the issue, it does quite a lot by itself IMO.)