Ta-da! Here it is.
I now think I made the original dough a little TOO moist. Especially after having watched the NYT video of the procedure which Nina kindly directed me to (not sure how I missed it, actually). When Lahey mixes the dough (nonchalantly and instantaneously with one hand) it looks sticky but not LIQUID the way mine did. Just points out the importance of not relying too much on measurements. This meant that when I got to the "form it into a ball" stage (right after the 15-minute rest) I had a little trouble ending with anything resembling a "seam" anywhere. Similarly, after the "rise-between-the-towels" stage the dough was STILL quite wet, and not so easy to extricate from the lower towel. Bittman notes almost as an aside that he had a number of "failed attempts" that were still better than almost anything you could buy. I agree with this 100%. I'm definitely starting with a little more flour (or less water) next time, but this loaf is heavenly. I'll be making it again and again.
Probably the most important innovation here is the way in which baking the moist loaf in a preheated COVERED pan deals with the all-important need to introduce moisture into the oven. This is essential for the crustiness we're looking for. And I am VERY pleased with the crustiness of this loaf! Professional ovens, as I learned at the CIA, have automatic sprinklers built into them. Home cooks, lacking these, are variously advised to throw in a few ice cubes, use a spray bottle to spritz the inside of the hot oven, or put a pan of water in the bottom, all of which I've tried, none of which is ideal.
I discovered in my cyberfiles (courtesy of the amazing "Zoot" - worthy of a future post) another recipe from the NYT that I had clipped but never used that comes very close to utilizing this technique. Here it is suggested that you preheat a large heavy pan in the oven, as we have done, but THEN, instead of putting the dough IN the pan, you put it on a baking stone and then use the hot pan to quickly COVER it up, like a cloche. You remove the pan toward the end of the baking period. Same thing, really, but gives you a lot more leeway in terms of different shapes for the bread.
Oh, and now I notice there was an accompanying article by Kay Rentschler from the same May 26, 2004 paper which credits Sullivan Street's Jim Lahey for the idea. Maybe Mark Bittman has been prowling through the Times archives.
As to the flour type: at the CIA we were told that using all-purpose hard winter wheat flour was best for these holey, crusty, "artisan" breads. The protein content is 11-12%. Official "bread" flour is a little higher in protein (11.5-12.5%) and better for "quick breads", Pullman loaves, and soft rolls, according to the handout I have before me from Chef Jurgen Temme of the CIA. The Rentschler article confirms this. (And oops - I now see that I incorrectly referred to a "poolish" as a "biga" in my first post. I'll fix that.) I'm actually not sure what brand flour I was using - whatever was in the canister! I'm guessing it is King Arthur unbleached all-purpose, since that's what I normally buy.
And as to the "folding" step which Pat G forgot, its purpose is (and I am paraphrasing from Chef Temme's notes again): 1. to expel gas and introduce oxygen 2. To move yeast cells to a new food supply 3. to equalize the dough temperature. Probably more than we need to know - just try to remember next time.
So that's it. Apologies to readers who are not interested in this subject. As if they are still with us!
Update: I've made this three times now, and each time was better than the one before. The firmer dough, using the 1 1/2 cups of water made a product that was much easier to handle. And finally, on the third round, I had access to a supply of wheat bran which made all the difference in terms of non-stickiness, and added a nice, nutty element to the crust. When I make it next, which will be soon, I may dispense with the towel altogether. I know that professional kitchens use special canvas for this. But I have a wooden peel that I use for pizza. I think that if I sprinkle this with the wheat bran and then let the dough ball rise on that, covered with a bowl or towel, I'll be able to easily slide it right off into the hot pan. (I'm using a 40+ year old Le Creuset casserole which I know I'm lucky to have.) The risen dough is just large enough that it's a little hard to handle without deflating in the towel-to-pot stage. Oh, and I've been using a 500 degree oven with excellent results. (Using an oven thermometer, so I know it's there.)