You must remember that you are operating a relatively powerful corporate aircraft, when the regulations were written this wasn't the case, you are also assuming that the aircraft has a better climb gradient with a lower Flap setting, once again this isn't always the case.
Under FAR25, the aircraft has to be certified to meet all the required gradients with an engine out, this information is only applicable to us when we need to clear takeoff obstacles. How do you protect yourself for clearing the obstacles if an engine fails right after you have retracted the flaps?
Mutt