Cyclists too! Interesting to observe in the many CommuterCam videos on you tube how many cyclists (incidental to the point of the footage) fail to indicate or shoulder check when pulling out past stopped traffic or changing lanes
I know what you mean, it can be a quite distracting when anyone, cyclists included, hasn't indicated their intention. However, there are situations that I sometimes feel I can't arm-indicate when cycling because of the amount of traffic and the road surface (seriously). I hope that a shoulder check and my position on the road is enough of an indication in those situations.