Originally Posted by zbenye

żLooks like I finally managed to post something in a way that wasn't an immediate give-away? Or perhaps it was incoherent, as WWE would ridicule.

By now I've found a handful of origins out of which this works. In a day or two I'll post the reverse availability C2-C1, which may help in identifying additional potential origins in C1.

I'd be interested to know if my OP was enough for anyone to find it, who didn't already know it. Or maybe y'all already knew it (the PMs indicate otherwise).