The photos are good and may make it punch above its weight somewhat, but who builds this sort of thing now? And why not? It's not portable, moveable yes. Operational? Depends. Would I build it? Probably not. Though the concept always stops me dead as I find it thought provoking. It's a trainset, but is much more than that term implies.
This is what I was originally looking for and is the same thing but on speed. Built by local (to me) pro modeller Brian Taylor, it forces some fearsome model making into a fearsome space. 1st rad curves and some slightly diddled with chassis in 3' x 3'10".
Both these layout have some sort of off-scene storage at the rear , which kind of defeats the object. Selfold I would have a crack at, though would it work as well without the NG? It would fit in the car, but how would you support it? I seem to remember that Brian displayed it fairly low, obviously aware that it was appealing to small people, but I can't remember how the wings worked. This would need extra boards and an awkward support system.
The problem here as always is one of transportation, but with no shows at present that suddenly seems less of a factor. Would it be stand behind, as per these two. Or stand in the centre a la Mannin Middle here. At its raw basic I can stand in the middle of the above circle. OK so it's like a hoop skirt, but you can see the basis and work outward and complicate as you go.
Trying to (literally) square the circle with baseboards is where the whole thing begins to unravel with leg systems as much as anything. One to park at the back of the brain for future.
As a PS Giles Barnabe emailed this. 32" square using the old Setrack curved points.
PPS. I've been nudged to add that if you click the 'inspirational layouts' tag you'll get the previous nine. Mostly posted in 2014. And there was me thinking it was last year.