Just recognized your name/avatar/thread from PolyPercs and had to at least stop by and say hi. I took your poll; I agree there's probably some crossover in principle, but I wouldn't make any commitments about how *much*
crossover I think there is. I know the originally-cited study shows some evidence of sex-work crossover.
I'll also say that in the about-four years that I've spent on poly forums (mostly Ppercs, but anyway), I've observed quite a few cases where swingers were transitioning into poly, or where already-poly persons are swingers also. So I'd estimate there's considerable crossover between swing and poly.
Anyway, hi, always nice to see a familiar face.