Tartine Semolina Sesame Loaf

Hi Everyone..

I tried to bake the Tartine semolina flour sesame loaf this weekend. I made sure my starter was active and doubled within 4 hours. I used it at the 4 hour mark when double and followed the recipe rather closely other than to make a smaller amount - 1/3rd of the recipe in proportion to see how it turned out before committing to a bigger loaf. Everything looked fine along thew way, and I cold retarded in the fridge after three hours of bulk fermentation and half hourly S&Fs. Given I was using a 1/3rd recipe size (the recipe makes two full loaves), it spread out a bit in my basket overnight in the fridge as the dough amount was a bit small for the basket. The taste is fine, although a bit moist given it's dense. But I'm not sure what I did wrong. Anyone have experience with this loaf/flour?

There are only two things I can think of doing wrong : a)  maybe to have let it bulk ferment a bit longer - the dough might have just about doubled in three hours but maybe not quite.. or b) when I shaped my loaf before placing it in the basket/fridge maybe I worked it a bit too much?

All advice welcome. Thanks! bake happy.. bread1965