John - thanks for a truly excellent post.
Regarding the 'flapped delta' nature of the '144, would you say that it was more similar in nature to the Vulcan at low speed, rather than a slender delta such as Concorde? I only ask because, on a programme about the Tu-144 on Discovery, there was a clip of a very poor landing in the Tu-144N. It showed exactly what not to do with an all-elevon jet if you bounce on landing. The pilot clearly checked forward, 'adverse flap effect' promptly got it airborne again, briefly, then it started to descend as it ran out of IAS. So the pilot checked back, lost the additional CL from downward deflected elevons and thumped it in fairly firmly. It's interesting to run such clips on a VCR at high speed, flight path deviations are very obvious then!
Incidentally, what's the betting that the accurate touchdowns of which you wrote were probably down to some simple bit of wire poking out of the airframe which the pilots merely aimed at the touchdown point? That or some equally simple but effective Russian solution!