> Can you say more about that, or provide a link?
>

natural leavening requires the development of gluten then the yeast eat
sugars and fart carbon dioxide (and shit alcohol in the case of
fermentation.). the yeast farts are what leavens the bread and the gluten
development aids in holding the yeast farts. chemical leavening on the other
hand is a different beast all together. this link will probably tell you
more than you ever wanted to know about chemical leavening --->
http://users.rcn.com/sue.interport/food/bakgsoda.html