I was inspired by how simple this 1-2-3 Sourdough recipe was, but my first try was less than successful (OK taste, but dense brick crumb). So, taking the advice everyone was kind enough to offer, I tried again.
I used the same levain (100% hydration, nothing but water and Brule Creek Farms dark rye flour). I keep it in the fridge, so I took it out and fed-and-dumped it once a day for three days until I had a doming rise and levain that (according to the Tartine test) floated in water.
Based on previous advice, I started with more all-purpose flour and less rye than my first try to give the loaves more of a chance - here's the formula I used (PDF). This led to a dough with an overall hydration of about 71%, something I'm used to. I mixed the ingredients, and left them to ferment for about 15 hours (before I went to bed, 6 hours after mixing the dough, it had risen maybe 20%, so I left it overnight at about 64F - this led to dough that had more than doubled overnight.
Next day, formed the dough into boules, and set myself to proof the dough for 4-5 hours. Two hours later, though, the dough looked risen enough, and passed the "poke and 1/2 way back" test...
... so I scored them...
... and loaded them into the oven. They baked at 500F for about 5 minutes (steam with water squirted on the inside wall of the oven), then 30 minutes at 400F. Here's what they looked like right out of the oven....
... a FAR cry from my first attempt:
After letting it cool, the crumb & taste test:
Although not as airy as some sourdoughs I see, I'm very happy with the crumb. The sourness is about mid-range: not the sourest I've tasted, but not subtle. I think I'll be using this to accompany strongish lunch meats or cheese.
It was about 14 hours between the last feed before the dough and my using it - I wonder if using it sooner might make the sourness a bit more subtle? Don't get me wrong - I like the reasonably assertive, but not overwhelming tang, but I'm thinking of ways to make it a bit less tangy.
Thanks to everyone who helped me get to this point - I'll let you know how future loaves turn out.