I see what you mean, and sorry, I hadn’t previously associated your two comments as being the same person.

I think that your second hypothesis is more or less correct. The long gluten chains give the dough the elasticity to stretch and contain the bubbles.

I’ve heard other people say that a sourdough works better, as well. You have a good point, maybe some combination of a yeast and a bacteria that act more symbiotically together could be beneficial.

I’m not sure how the bacterial action that creates sourdough improves a gluten-free bread, though. It seems intuitively unlikely to me that it would be by breaking anything down, as we want more elasticity that, in wheat based breads, comes from building up the long gluten chains by kneading.

Maybe it is the bacterial bodies themselves? Xanthan gum is very commonly used in gluten-free flour to help it hold together and have more elasticity. Xanthan gum, as I understand it, is derived from the mash made after fermenting sugar with a specific bacterial strain.