In reply to tehmarks:
> But surely the solution isn't to use a different grading system, but to remove the inconsistency?
I think that is impossible due to the variation in what people expect from a tech grade, and what a route delivers. John's illustration of how the nature and position of a crux move can affect what tech grade a route is given is just one of many variations that can change a tech grade. How long the move is, what comes before it, what comes after it, what type of climbing it is, which crag it is on, what the rock type is, who graded it in the first place, ... all these change massively from area to area.
Even if you could drill down and define what is meant by 'a move', sort out some system for making allowances for the position of a move, and propagate this over the whole country, I still don't think you will have done anything very useful since there are so many specific variations in people and climbing styles.
The good thing about Font and Sport grades is that aren't as ambitious, they are just an attempt to come up with the overall difficulty of the route/problem. There are still big variations but the system is more flexible and less demanding.
Trying to actually crystallise the hardest move on any route is very much in the category 'how long is a piece of string'.
Having said all that, I don't think we should get rid of tech grades (except for boulder problems maybe) but we should learn to lower our expectations of what they actually mean.
Alan