I think about severe 4a is more realistic. Nice line, but a bit short. The line is a diagonally left rising traverse up a slab underneath a large overlap. Mark, sounds like you did a direct start into it.
Tom Last - 2nd - 14/Nov/12 with Chester

I think this was the route although certainly not vegetated. Climbed a steep crack/ groove then the bulging slab directly above
The Pylon King - Solo RP - 11/Nov/12

D Berry - Solo O/S - 03/Jan/09