Nah...unless you lost me entirely.
As a rule though...the shoulder becomes part of the neck when you neck a case UP, not down. That's because the shoulder brass is typically a bit thicker than neck brass and necking up...the brass has top come from somewhere, right? Sure, there might be exceptions to that, but I've never seen it. Still, possible, though, I suppose.
I'm not speaking theoretically but strictly from experience. as well as just logic. So yes, I guess what you said is possible in theory but I've just never seen it, nor would it make sense...over a bunch of different wildcat examples...fwiw.
Often times, just doing something trumps whatever it is we might rationalize.