“I’m a ****, what do you think I’ve done? I’ve opened a corner shop”
Yes, and he has the right to say that…it shows he has some kind of sense of humour about his background and obviously feels comfortable enough to share his humour with you, perhaps to make you feel more at home with him. It’s like when I share an Irish joke with my good friends – and I’ve told plenty of them on here. This kind of banter that goes on between friends is not black and white (oops, see what I did there?). Just because I tell an Irish joke to some of my good mates (and I include this forum as a place with which to share humour with “friends”), it doesn’t suddenly give all and sundry a chance to lob up to me and make out I’m a thick eejit, running around drunk with a pig under my arms.
Context is very important in these matters and usually, we’re all intelligent enough to judge each situation when they arise…obviously David Jason wasn’t feeling too clever when he chose to tell his joke.