I've never ridden the Three Shires Way. I live really close to Santa Pod though, is it worth a go?
Report it to the local council highway dept, they should get it cleared. I had the same problem on a bridleway close to Crowthorne, reported it, the following week it was removed.
Thanks for the heads-up Mojo!I've now done from Grafham to Santa Pod a mix of open grassy bridleway and on road with a few rutted bits around Yeldon.
The section from Santa Pod to where it crosses the A6 is mostly woodland and currently very wet, slimey and mostly deeply rutted by motorbikes and hard going (I came off twice - not fun when you're clipped in).
Unless you like getting muddy and fancy the challenge I'd suggest skipping that section and joining at the A6 adjacent to the Biogen plant it's then a very pleasant ride. If you make it to Grafham there's a couple of cafe's where you can get bacon butties and a coffee etc.
bob