In reply to Andy Manthorpe:
I did the walk yesterday. Ideal winter conditions, plenty of snow, blue sky and little wind. Approaching the ford I met the farmer who's land it is on. He told me to carry on down and if I could not get across, then I was free to follow the river up through his fields, rather than have to double back. Nice gesture. Any way I crossed at the ford and enjoyed the four famous peaks, before getting back to the car under a beautiful Crescent moon.