To riff on what the poster before me said ... if the car was to your left and you were turning right ... what difference would it make to your life if he doesn't wait for you to move off first and complete your turn? And what do you mean by "the proper hand signal"? The proper hand signal for a bicycle turning right is your right hand pointing right. I personally wouldn't assume that a driver to the left of me would even see my right hand, and if I used the (not unique to bicycles) upraised left hand to signal a right turn, yah, the driver might see it but would likely not interpret it as anymore a request to wait than if it was a car that was turning right in the next lane. If we are going to rag on drivers acting badly we should be clear on what 'badly' actually is.