I just made Peter Reinhart's focaccia from the BBA, and used the book for the first time (vs internet recipes which aren't always as accurate). I carefully weighed all the ingredients, down to the yeast and salt. While mixing, it says to add flour "as needed." What is the purpose of measuring flour and water percentages so accurately if you're just going to add flour until it feels right? It's also hard to go be "feels right" because every bread has a different hydration and feel. When you first try a recipe, how do you know how much to add? I add heaping tablespoon of flour at a time but is there another way? The description is until it slightly pulls away from the side but not the bottom--there are many degrees of that. People always talk about how baking is a science but when you get to this point, it really is an art.
BTW, the focaccia turned out wonderfully. I was a little worried about it being over hydrated (still think it was, had some trouble dimpling) but it's still good. If you try this, watch the herbed oil--mine overflowed the baking pan and I have a mess to clean up in the oven.