Sorry- I have to step in again. The hazards of taking off with even small braking applied outweigh the alleged disadvantages (which I don't agree with) of the delay of a few tenths of a second of having to lift your feet about 3 inches to apply braking. Take-off how you like, just be doubly, trebly sure you don't have even a minute amount of braking applied! It will be the end of a promising career! The only way to be sure is to have those heels firmly sliding on the floor. I have seen a pilot cause an abandoned takeoff at 120 kts. because he did not have one heel on the floor in a strong crosswind. I've seen someone screw up because of it- I have learnt the lesson. You can find any number of references to 'have your feet where you like'. But the system is designed so you cannot apply braking with your heels on the floor. You can apply braking with your heel off the floor. What more needs to be said?