What's Mallard raving about today?
Imaginary Outraged Readers.
The idea of inventing imaginary readers who are outraged is, at the same time, the most pathetic and the most self-aggrandizing thing I can imagine.
Slightly less pathetic than repeating the joke and then explaining it.
Most pathetic of all, however is that Mallard considers it a safety feature of his panel that the illiterate will not be incited to violence against teachers because they can't read. Which means he fails to understand that what is outrageous and offensive is not the lamely satirical incitement to violence, but the very real mean-spiritedness towards a group of people who deserve nothing but respect.