As a Bodhran player of long standing, twenty odd years now, I wholeheartedly agree that a bad drummer is the worst thing that can happen to a session.
I am also a Bodhran teacher and I try to instill a sense of courtesy in my pupils, for example, if they go to a session and there is another drummer playing put your drum down and await your opportunity to join in, if an opportunity does not present itself then don't play you will win respect for your attitude. I also like to remind drummers that the Bodhran is the easiest instrument to play BADLY and perhaps one of the most Difficult to play well and sensitivly.