Thanks for the feedback, everybody, I appreciate the contribution to the discussion around my paper.
There's a lot to respond to in this thread by now; to make sure that my response isn't overly long for an email, and that it's discoverable outside the reflector, I plan to explain my thinking through the paper system, via a new revision of P4030, and/or a new rebuttal paper to P4279. I'll update this reflector thread with links once I've had time to collect and write up my thoughts properly.
Thanks,