I just got the King Arthur whole grain baking book, and was disappointed to find that nearly every recipe calls for a stick or more of butter. That would bring out the whole grain goodness :-), but I'm wondering about substituting a light flavored olive oil in some of the recipes, and wanted to hear people's experience with substituting oil for butter in baking. I know that I need to cut back the oil ~25% to make up for the non-fatty part of butter, and there are obvious textural differences, so how can I up my chances of coming out with something good? I'm particularly interested in cakes and bar cookies. Thanks for your help.