Just for fun, I made a 1.8× batch of the tartine country loaf, but still made two loaves.
Overall they're great, if a bit dense. I theorize that the mass of the dough makes a more open crumb difficult at this size, but it could also just as easily be any of the more normal reasons.
Amazing the difference photographing in sunlight makes
These are some great breads and this might be one of those bakes that you remember for years to come.
It is a bit contradictory when you think about it to have open crumb and bread that is a little dense because really what we're after is something that feels light in the hand and also light in the mouth.
I do know that when I have a very large batch of dough that it does ferment more rapidly than if it's two smaller pieces of dough. So maybe that is what you experienced here?