In reply to Rory Shaw:
I thought Cockblock was given E5?
I think I'd give Bitterfingers hard F6c+, Cabbage Crack and whatever the E4 next to it is called are harder.
Some Lakes ones:
Fine Time - really only a short hard section but it's a real stopper.
Lost Horizons - very sustained until you pull back right in to the upper groove.
Burning Bridges - actually maybe F7a+, it's harder than something like Balas at Kilnsey but long legs makes a difference.
Some of the other "traditional" Lakes E4s have been upgraded to E5 - SOS, Gates of Delerium, etc.
Overall I'd say E4 sits on the F6c+/7a boundary, maybe two thirds of the grade band is F6c+ with just the harder end of the grade being F7a.
ALC