In reply to pec:
Obviously Stannington is shortish single pitch and a lot more solid. The thing is it's dismal: oh to risk death or injury or tetinus in a damp rubbish dump!
Those of us who climb choss do so for many reasons from the good to the bad: sometimes out of choice like Dave in that excellent film; more often because it's a small part of a larger classic route; sometimes because it's degraded over time (say frost action on limestone); sometimes because although we expected adventure the description was dishonest.
I wasn't frightened at Stannington I was more disgusted. To me it was in the fourth category where you could choose lower risk options. I can understand why some with transport problems might climb there during foot and mouth when nearly everything else is banned.
I've been most focussed on a Severe called Ossam's climb, which is a straight up piece of esoterica, just left of the start of the esoteric classic Cumberbund in the Manifold. I first did it by mistake trying to find the line on Cumberbund: it was looseish but fun with a solid tree belay on the midway ledge. 15 years later I tried it again and the surface had become fundamentally fractured such that no hold on the route was trustworthy. By the time I realised something was badly wrong, I felt it was easier to go up to the ledge, and abseil, than try to down climb but when I got there the solid tree had rotted to papier-mâché and there was nothing else solid. Having been at the convex brambly top before I knew it would be slow and complex process to arrange a top-rope so for some reason I 'turned my brain off' and carefully finished the remaining 20m of choss. I've never been so happy to pull on top-out brambles. I climbed it well but personally wouldn't chose to do something like that again. Maybe 4a X as a grade but its hard to tell in full focus as you climb better then.
In contrast I chose to climb Pickering Ridge in Dovedale, knowing its character... I remember it as good loose fun with a simul-abseil escape off opposite sides as there was no solid belay on top.
The loosest rock I've tried (and failed) to climb is a shale crag in a park near the railway in south-east Nottingham... that makes the rock in Dave's film look good! Worse than the shale bands in the cloughs under Kinder.
I've also been underwhelmed by the legend of choss: Wreckers Slab was pretty much solid where it mattered and felt more like a classic Severe 4a in Yorkshire grading. Quite a few north Devon climbs I've done were a delight and completely solid.
Post edited at 11:38