So Sustrans contributed £20000. Don't they check? Don't they care?
I'm afraid that Sustrans, already pretty low, are sinking rapidly in my estimation.
What does happen on surfaces like that is as it beds in is that the loose gravel gets swept into the less used edges which, when encountered in a deep drift unexpectedly - say when riding side by side with family, leaving them in the "good" centre and chatting away merrily - does have the resultant effect of reducing the total amount of loose gravel. This is because you end up removing a quantity of the same, embedded in your body.Mrs B suffered that problem once. Still has the scar on her elbow.
DNAHIKT
Incidentally, many Beeching-axed railway lines in our area have become cycle routes, but they too are mostly surfaced in loose gravel. Another opportunity missed.