In reply to Templeton Adams:
I found the stiffness of the boots (near fully rigid) was a great help, but I suspect that the first reply is correct and I'm just going to have to work out what "too wet" is.
As an aside I seem to remember that 5:10's canyoneer boot works on wet rock brilliantly (though this is unsuprising given it's purpose), but I can't justify a pair for scrambling in certain contitions.