No 'tis from a Cornish boy.
But nearby townspeople used to say about Saltash inhabitants :
'Saltash Rig - wet ass no fish' which means...( from an extract from a book of dialect...)
Saltash luck - Getting a soaking while doing a job. ‘A wet arse and no fish!’ (Saltash anglers fish from the bridge and catch nothing but the tide.)
Frank Butcher and I had some common acquaintances in our mispent youth so I thought a friendly insult was appropriate in terms of his 'Saltash rig ' semi-final experience