Helen: iirc the P-prefix thing was originally a side reference to Pyramids*, where the handmaiden Traci becomes "Ptraci" when she's outside the hero's kingdom (she speaks Ephebian with just a ptrace of an accent). But *agree* about the theraputic effect of laughter --- it oils the synapses summat wonderful. I do wonder what Sir Pterry would have made of He Who Must Not Be Tolerated.

* Corrections invited.