Sourdough Baguette

Baking appears to be at least as much chemistry as cooking, so I thought I'd better take notes as I'm experimenting with a new (to me) recipe.  Here seems as good a place as any.

Laur gave me a sourdough starter, and I'm playing with it.  Starting from here, making some adjustments based on the adjustments that worked for my other baguette recipe, and some from a page Laur gave me on making sourdough sourer.  Keeping the adjustments small to start, figuring I can tweak more later once I've seen how well it worked.

Fed 60g of starter (down 5g, for extra sour) with 70g water and 70g flour.  Using Gold Medal unbleached all-purpose flour throughout.  I was supposed to let that sit for about 6 hours according to the recipe - I gave it more like 15, because I didn't feel like doing the second step at 1am.  We'll see if that matters, but the be-more-sour guide recommends lengthening and slowing the growth stages, so I think its all to the good.

Mixed:

600g flour
187g starter mix (200 less the scrapings in the bowl, down a bit for extra sour)
400g water

into a shaggy mess in a bowl.  (I'll try this recipe in the bread-maker later, but I want the by-hand version to compare it to.)  Sit for ~25 minutes to autolyse without the salt (which I've never done before.)

Knead for 5 min.  Realise I've forgotten to add the salt before kneading; add 15g salt (up a bit for retarding yeast growth at altitude) and knead for 30 sec more.  Cover with a towel and let sit on the counter for an hour.

Fold the dough over itself a dozen times.  Cover with a towel and let sit on the counter for an hour.

Fold the dough over itself a dozen times.   Cover with 2 layers of plastic wrap (opposite directions, so it can rise without exposing itself) directly on the surface of the dough.  Put in fridge for 12 - 24 hours.

Ohhhhhhkaaaaay.  Didn't rise.  At all.  How is that even possible?