I think there's a lyricism, and a cadence in northern working class comics' speech, from Kay to Wood to Dawson, which appeals to the north-west, I like to think because we're nearly all Irish in some way, and we have an ear for it!
I can hear a lilting tension in northern comics voices, it's a poetic balance; I think it was Thora Hird who was credited with telling Victoria Wood how one the greatest things she ever learned in comic theatre, and which stood her in good stead through her career, was that funny lines didn't go: Dum-dum-dum-dum, at the end - they had to go: Dum-dum-DI-Dum.
It loses in transcript, obviously. But it's like the meter of a poem, it has an internal resonance that feels pleasing to the ear, warm and recognisably human. Surprisingly, those are the kinds of words used to describe this popular type of Northern humour...
Also, I think there's a willingness to experiment more with vocabulary. Just finding words funny just for the sake of them, Alan Bennett and Vic Wood and Peter Kay do that a great deal, you could list them.
And there's a pathos about northern working class humour. If I think of southern comics like Mike Reid, Harry Enfield, Jim Davidson, they have brashness and entrepreneurialism that isn't as common up north, ime.
The north's circuit of clubs has meant comedy has hothoused here for years. That's why we can throw up someone like Johnny Vegas, who's club act is hyper-lyrical, hyper-pathetic, often combative and orgeastic - and magnifies the strands that traditionally comprise northern humour to the max. His stage show is a revelation in improvisation, it's scary, and I think any scene that stretches from Cannon and Ball to Johnny Vegas has to be healthy.