Dan Henry built a couple of recumbent bikes and he might have put a Bummer-type seat on it. I remember a book that showed some of his experiments but I don’t have a copy.

In terms of the noseless/moving butt pad seats: they seemed to show up every few years at the bike shows, sell a few, then move to the blow-out pages. I recall the Easyseat showing up three separate times during my career in the bike business.