The Fundyscope was published in S&T in the early '90's, about ten years after your RTMC sighting. I'm thinking '91, '92 maybe, I was just looking at it a few weeks ago. But I recall it as having a horizontal OTA. A tilting flat on a polar axis reflected horizontally to a standard Newtonian primary, which reflected it back through a hole in the flat, to a stationary eyepiece. Didn't look too practical to me, a regular Newt of similar size on a GEM seems much easier to setup and deal with, and a stationary, perfectly horizontal eyepiece has to be at exactly the right height to not be a pain in the neck.
You know? That might have been it. Or something similar. Biggest drawback is that the flat would have to have a minor axis as big as the primary. But the tilting single flat would only have to pivot less than 45 degrees either side of the celestial equator. Since the ota would double as the polar axis, the scope could be pretty light and compact. That's what I remember about the one I saw.
I'll have to dig up my digital copies of s&t and look up the Fundyscope.
