Fondly remember this show, the name of which I'll avoid to swerve any clumsy, overzealous filters. It spawned Rab C. Nesbitt ... and the tales of Stoneybridge...
This is a simple example of stereotypes being used to challenge conservative notions of identity. Behind the preferred reading here is the assumed knowledge of the sensationally conservative publishers that dominated much of the Scottish press.
I grew up reading the likes of The Dandy comic, sold UK-wide (still; think Dennis the Menace), produced by DC Thomson in Dundee, as austere and stern a publisher of fun material for kids as could be imagined. Any doubts I had on this were reinforced in my 1st year at IGS, when an SEN assistant turned out to have worked there and shared a few reminiscences.
On the surface then this is a simple culture clash between young(ish!) comics and the old-fashioned, highly conservative Establishment that held sway in Scotland, seeking to breakdown that essentially Presbyterian stereotype - which has close parallels with the Yorkshire stereotype by the way.
Where there is some polysemy is in their use of stigmatised social minorities to make this satirical distinction and break. Does this simply reinforce those stereotypes and cultural values; reinforce some parts of the cultural hegemony of conservatism whilst challenging others? Is the whole piece counter-hegemonic by actually making single mothers and homosexuals part of a new normative representation of Scottish society? Or could there even be an Alf Garnett effect - in the notorious 70s sitcom featuring the character, the liberal characters sought to challenge racist attitudes but unwittingly spawned a racist hero!
Semiotic approaches are valuable, but, especially as you progress through Media Studies (and this applies to coursework planning and Evaluation too), you also need to engage with audience theories. These are often highly contradictory - providing you with the opportunity to provide your own view and voice on this highly contested field.
With this sketch there is also the reception issue of its age and current events. I happened to stumble across it moments after reading a news piece in which the Vatican condemned the vote in R. of Ireland legalising gay marriage as a "defeat for humanity". There are dangers in reading a text of applying the values of 'our' times.