The brake bleeding procedure is to pump the lever/pedal, hold lever/pedal and then open bleeder valve and then tighten, I think before end of travel. You're not supposed to pump the lever/pedal when bleeding as this may draw air back into the system. Well as long as the hose is full of fluid does it really matter? I mean couldn't you just pump away and then tighten? Or does this cause air maybe to be drawn into the system from around the threads?