To the annual conference of the Learning and Skills Development Agency last week, where the hired entertainer forgot the golden post-16 rule - never, ever mention teenage sex.
Mitch Benn, the 47th funniest man in London according to Time Out, got a decent laugh for his blow-job joke at the quango's gala dinner in London.
But you can't please all the people. "Completely tasteless," was the verdict one delegate was heard to mutter.
The matinee had been a bit tamer - the entertainment being provided by the much-loved music hall act Ruth Kelly. No blow-job jokes but some very exciting "key messages", I'm told.
Even so, the afternoon wasn't without a bit of slapstick. Sir Geoffrey Holland, the LSDA's chairman, wiped his brow with the back of his hand while standing in the wings, forgetting that this was the signal for the floor managers to start the conference with a burst of music.
The music was supposed to trumpet his arrival - along with Ruth Kelly - on the stage, but by the time they appeared the place had fallen into silence.
Word is that someone tried to start a chorus of "We want Ruth".
But it never caught on.