I'd had to sign out of this account and sign into another one quickly whilst writing that last post, and had forgotten to re-sign in. Thought I'd lost the whole thing, glad I hadn't. I'm lazy and repetition = bad.
Anyway, forgot to put this in the last post - generally, product information from manufacturers is about as interesting as watching nitro-cellulose coloured lacquer dry on an aluminium frame (which it never seems to, properly), but this is actually interesting and almost got an audible "aaaah" from me. G-Sport George knows what's up, and what is currently up is the Birdcage rim.