Bleurgh indeed.
I'm re-reading Rivals and just got past the bit with the crumbling lake path, and I am struggling to place together what seem contradictory ideas about the physical capability of the girls! very possibly I'm just looking for a truth that isn't really there
So, because they can't return the way they came, they need to take a longer, steeper journey home. Yes, it's a long and arduous climb, but it's over and they're carted home by around 4/5pm, and the next day half the Saints are apparently too done in to even get out of bed and their Matron is "worried and irritable", the rest of the staff "looked troubled". These are not very young or otherwise physically vulnerable children. Is it that smaller, more sedate, less well fed young ladies in the interwar period just weren't as fit and strong as today? Does it reflect a now-outdated notion that it paid to be cautious about physical exertion and other stresses?
But... the walk that the Saints were already doing, past the Dripping Rock to Gaisalm and back is already hardly a gentle stroll. (Can personally attest, having done it with 18mo in sling, and with my 7yo and my mother in tow - by the time we'd made it from Briesau Pertisau to Gaisalm, we were glad to sit, eat/drink, and get the boat back!) And I'm minded of the distances the girls often cover around the Tiernsee - I've read the suggestion that EBD 'shrank the lake' and that's how "being back before breakfast" was possible, and also the counter-suggestion that EBD was talking about hale and hearty girls who happily walked much further and faster than middle-aged Chaletians making their pilgrimage decades later!
I suspect the simple answer is that I'm looking for sense where there's none to be found, since it's pretty inconsequential, but either I'm missing some important context in health/fitness expectations of the time, or it's another contradictory EBD desire to do muscular Christianity and delicate heroines at the same time.