I did a variation on that loop today on the CX bike. Comfortably under an hour to get from Hayfield to Edale via South Head, Mount Famine, Roych and Rushup although once I got to Rushup I took the road as the crosswind on the ridge would have been horrendous. I reckon doing the ridge run would have made it more or less bang on an hour to get to the Penny Pot Café.
Once up on Mam Nick I took the First Descent route off (by the bus stop) down to Edale. Most of the route was amazingly dry although the bottom of Mam Nick descent had a 30m section of totally unrideable quagmire.
Came back up Jacobs Ladder then may have accidently strayed onto some FP after that… The headwind on the way home was awful. Could barely stand at the summit of Jacobs.
Doing it on a mountain bike would make the descents a lot quicker but the climbs a bit slower, not sure how that would balance out over the course of the whole ride. I was surprised at how well some of it has dried out though – Broad Clough usually turns into a hub deep mudbath at the first hint of any moisture but it was all riding well today. The extra stone packing further up Roych Clough is all holding up well too – have they actually banned 4x4s along this section now?