I have honestly never heard of such a thing. It sounds wrong, but I suppose many things do.
Actually, on a related note, I'm getting slightly sick of people trying to zhuzh up the prawn cocktail. It's fine if you want to eat a prawn cocktail, ffs! You don't need to deconstruct the ****ing thing in order to make it OK. Prawns, lettuce, pink gloop - bit of bread and butter - lovely. Stop ****ing about with it.