Really, really annoyed. Just got a ticket for undertaking on the M3. Didn't realise it was Charles and Camilla with a police escort travelling slowly in the middle lane. I was in a hurry so went down the inside to take the next exit. Blue lights and a motorcycle cop stops me short. He just looked at me and wrote the ticket. 'But why? says I. 'Sorry mate', says the cop, 'but you passed the Duchy on the left hand side'.
That doesn't work, as the Duchy consists of the land and holdings, not the actual person who is the Duke of Cornwall.
Even the joke about why Prince Charles likes to sail to Cornwall via the English Channel and not the Bristol Channel is questionable, as the county of Cornwall != the Duchy of Cornwall, and the Duchy has as much land outside of Cornwall as inside it.
https://en.wikipedia.org/wiki/Duchy_of_Cornwall