Yes, flashing lights means "I am here", not "pull out regardless". One of the worst examples of this was when I was cycling to work on a country lane, I was approaching a left turn with a car waiting to turn right and an oncoming car. The oncoming driver (completely pointlessly, as the road was empty apart from us) stopped and flashed their lights as a signal for the waiting driver to pull out, right when I was about to pass in front of them! Fortunately the driver had seen me and stayed put, this oncoming driver still flashing, apparently completely oblivious to my presence and why the other driver wasn't moving.