Control: what was the "important distinction" between Salford and Manchester?

Well, they're officially separate cities, even though it's hard not see them as one. I read once that Salford was only granted city status back in the 1920s as a sop to the council or something. I guess the humour in the line comes from the fact that Salford is tired of smashing its head against a wall reminding people that it's a separate city.

(and Wilson is from Salford)

Yes, I'd imagine he was just being silly about these little lines that divide cities that people get all crazy about.

This reminds me of John Cooper Clarke appearing on Kazuko's Karaoke Klub in the late '80s, being interviewed by Frank Chickens - "You are from Manchester, yes?" "Well, no, Salford, actually." "Oh, sorry." "It's alright. Just different sides of the River Irwell, really. Same laws and everything." "You are very profound." Something like that, anyway. I think Frank Sidebottom was on it too. Golden memories.