In reply to Robert Durran:
> I don't think that is thought generally to be the case. I am an exceptionally poor acclimatiser and despite being as fit or fitter than others on every trip I've been on to the Greater Ranges, I have been completely outperformed by everyone else at altitude - never really achieved anything!
Yes. Anecdotally, having been involved in running commercial expeditions for 20+ years there is undoubtedly a correlation between the very fit being poor at acclimatising. Not everyone, of course but I can think of lots and lots of cases. If someone puts "Sub 3-hour marathon" on their experience form, I worry.
Wrt Ama Dablam, it's basically a big, rocky Alpine Difficile. Mostly rock in recent seasons apart from the top summit slopes, so you'll rarely swing an axe, even if you never pull on any of the fixed ropes. The crux is VS 5a, so obviously you're going to use less energy the better you are on rock. Being comfortable in big boots on VDiff is basically where you need to be.