In reply to Graham:
Well done Graham! You're getting there. But I think I can improve on it. Each climb needs its own grade, which will allow it to be uniquely located wrt other climbs.
I call such a system a 'graded list'. This allows a climber to confidently launch up any route below the highest one he or she has successfully led, and to make progress up the list in the confident knowledge that the next one up is pretty much the same as the last one, only ever so slightly harder.
Our good friend Mike Whitaker has agreed to spend a few weeks compiling such a system for the whole of the UK, by creating consistency between all the existing variants on my novel idea. I'm sure you will agree that such a system cannot be improved upon and will settle all arguments once and for all.