Reply #80: It certainly makes sense to preheat when using baking powder --

[emcguffie]

-- or particularly double acting baking powder, because it works twice -- once when liquid hits it, and again when heat hits it.

If the biscuits (which only need to cook a few minutes anyway) start to bake and the structure is fixed, then the gas expansion that comes as it heats up can't increase the volume any.

The same principle, I think, is in effect with baking French bread and providing steam to keep the dough soft, so that it can keep rising with the second push the yeast makes with the heat. How much more can the dough rise before it is too rigid to rise any more?

So I guess I'm saying it has to depend on what you're doing. Baking is indeed much more complicated than roasting, I think.