Be my guest sticknruda, I learned a lot from creasing a Cessna:
(1) Not all instructors know everything.
(2) Read the %^&*ing book and follow its instructions.
Pulling the flaps out during rotation is asking for trouble. For a start on a Piper, you need to reach down to the floor. On a Cessna you need to either place a switch in a particular setting (you cannot rely on those little plastic ridges) or hold a switch down while watching an indicator. Quite a lot of C172's don't even use flap on short field anyway. All you need is for some other problem to appear while you are performing this act and you are stuffed.
But go right ahead and develop your own technique. Its not as if anyone took any care writing the manual, you obviously know better.