Re:
That tends to be a common misconception. I've looked at a lot of Rourke frames and bikes on line, before and after buying mine. And while it is true that the majority have wrap around seat stays, there are a good number, like mine, that did not.
I'm waiting on more detail from Jason Rourke on the bike which was custom built for the original owner who I bought it off. I have to assume for now he simply specified none standard Rourke seat stays.
There's no doubt about the authenticity of the bike though which was sized and fitted by Brian Rourke himself.