In reply to TobyA: I'm from W Mids too, I first climbed at Llanymynech in 1970! The rock was only just hardening then...
Also I used to climb with Tony Booth, a wacky character from those parts who was (probably) a spy in the pay of the USSR but did the 1st aided ascent...
Anyway did Black Wall a few years back, I led most of it(!) then backed off, then my mate led it in the rain and didn't seem to have too much problem. (He was good, but IIRC the pro is great.)