Restaurant sketch

I just watched the sketch where Eric Idle plays a wife who talks non-stop and ends with "rhythm method." My question is how could he also play the uneaten vicar standing in a vat nearby in the same sketch? He was not on-screen in both guises at the same time but it was a cutaway that looked like the same set.



"I will not go down in history as the greatest mass-murderer since Adolf Hitler!" - Merkin Muffley