Rhys – is that Rhys as in the one that climbs with Jack?
We got on ok bivvying using a jetboil, but the new MSR reactor does seem to work well up at altitude in the cold. A mate got on really well with it in Alaksa this spring.
Food wise – as Steve says, routes like the piere allain have enough stops that you don’t need to survive on gels. I always get on well with bagels, peanut butter and honey (or jam). I remember on the Eiger finding a big (200g) bar of chocolate was a winner for the bivvy! I woke up roughly hourly through the night and ate another few squares. It seemed to keep me warm and help recovery. If you know you’re bivvying before, and maybe after on a route like the PA – go reasonably heavy on the approach! Bring cookies or whatever nice snacks you like.
Andy K always swore by adding olive oil to any dinner. You could bring a small bottle and just pour it straight into your freeze dried? Steve (unsurprisingly 😉 0 is spot on with the advice of keeping the food pouch in your jacket. Just be careful not to spill any!!
Nice one getting on the PA early December!