Can I just use regular wheat flour instead of the pastry flour?
Whole wheat pastry flour is much lighter and fluffier than whole wheat flour, which can be heavy and grainy. Whole wheat pastry is similar to all purpose, only it still has all it's nutrients and is less processed. White whole wheat usually works alright, and oat flour does a pretty good job most of the time too. Other whole wheat flours (like regular whole wheat flour, or whole wheat flours that are lightly tan in color) generally do not work or the results are dry and dense. Regular whole wheat flours tend to be thirstier than whole wheat pastry and much heavier and grainy. Check out my earlier post on the different types of flours for more information on their differences.