So that big honking layout built by Tony Lash would by definition qualify as 3 Rail Scale then, correct Allan? His layout is/was head and shoulders above a number of 2 rail scale layouts I've seen.That's what a majority of us would consider as a 3 Rail Scale layout even tho he had un-fixed pilots, tinplate profile wheels and "lobster claw" couplers.
So in a nutshell, if the layout has a realistic design, top notch scenery and buildings and realistically weathered rolling stock/motive power but you could still plop down an old Lionel 1666E and a string of sheet metal passenger cars on it and run them if you wanted that could possibly considered as a poster child of 3Rail Scale?
Man, I'm gonna have to up my game for my next layout!
Jerry