I live in Pateley and work in the TIC. One day would be very gruelling. The hardcore guys tend to do it in two, and stop here. First day is all up and down, but shorter day. By the time I see those guys they are nearly all pretty ruined, and often they have planned to go on to ripon but reach us and sack it off. that leaves you a second longer but far flatter day.
If you do do it then I doff my hat to you sir. I would need to be really fit before attempting.
Please do watch your speed coming down greenhow too, the corners are sharp, the road surface ****, and the hill steep. People have gone off the edge.
Would also depend if the wind was on your side as well.