Morris was initially influenced a lot by Lewis-Smith and there was mutual respect. I think after Morris started to get a lot of success on the radio though, Lewis-Smith got a bit jealous and accused Morris of ripping him off.

Here’s what I was getting my information from, it includes the Guardian’s Feud’s Corner article about them falling out (and further up VL-S’ Day to Day review) but, that is all itself, apparently, part of a larger prank:

The feud between Morris and Lewis Smith is itself a hoax. The pair, who regularly drink together in the Groucho Club, tricked The Guardian into thinking they were deadly enemies as a publicity stunt. For their pains they were rewarded with a ‘Feud’s Corner’ feature in 1992. One would expect The Guardian to check a story like this more carefully since Morris candidly admits to orchestrating letter campaigns against his own shows. He claims this is “a time-honoured technique for enhancing your notoriety. But it carries a risk: five years ago I unleashed such a convincing tirade against my own work for a radio station I complained myself off the air.”

Source

I suppose, if those two put their heads together, it’s no surprise we rapidly getting into prankception where we can never really know what level of the hoax we are at. That’s a good one, as it’s had me fooled for 30 years.