Ger:
Hi or lo is important, sure, for the protection of your ankles, but there is something even more important than that, the bones inside your feet.
More important than 'hi or lo' is the soles of your shoes, they should be very RIGID, and give your underfoot cavity good support.
The Camino I know goes over absolutely unforgiving hard surfaces, I estimate 99% is asphalt, concrete, gravel roads and rocks.
Walk that in soft shoes for several days in succession, with weight on your back, and maybe with some overweight on your body itself, and your inner feet bones can get a problem that will not go away again.
'Marching fracture'. I got that when I was a soldier. The inner bones of your feet can get 'softened' from ongoing load changes -severity and/or frequency- when walking. Over time, a friction develops inside the bone structure, bone tissue is irritated and gets ground to a kind of meal, and is pressed out from the bone to form a 'callus' on the outside. By then, the bone tissue itself and the skin of the bone is already irritated, meaning: you feel increasing pain inside your feet, with every step. End of Camino, very likely.
You best protection against that is -besides keeping the weight of yourself and your backpack low- to have your feet in shoes with rigid soles and maybe profiled inlay soles that strongly support the horizontal 'middle' bones of your feet.
We got good advice and shoes, and went well prepared, and my 'marching fracture' -which really is a 'fissure'- never returned.
We too have seen many people with 'light' shoes on the early stages of the Camino. But I also have seen some limping, and one giving up after three days. His feet just wouldn't take it.
Buen Camino!
Claus
