Guinness here in Ireland comes in two varieties ,
The Guinness Draught from the tap , its viscous , not gassy , has the thick creamy head and needs first and second pulls by the barman to get the required finish, its served chilled . Then theres the Guinness Extra Stout , that comes in a bottle , its more like black beer than porter , its fizzy , has a more frothy head than the Draught variety and is usually served at room temp. Of course Irish pubs the world over serve the 'black stuff' in the time honoured way , 3/4 er's on the first pour then once its had a minute or two to settle the correct amount of head is topped off , the Guinness tap has two modes , pull for main pour then push the tap to get the head .
My guess is most UK pubs just do a standard one pour method for Draught Guinness if they have it , then again if you went up Killburn or other places ex-pat Irish tend to congregate you have to wait the extra couple of minutes in the time honoured tradition , real stout men have the timing down to a fine art , a nod and a wink to your friendly barkeeper before the previous pint is gone ensures continuity , thing is even with the two pour method the pint itself isnt ready to drink without at least another few minutes settling time , so your always one step ahead of the lager drinker .
Being a Corkonian I'd highly recommend trying the other two locally made black beers , Murphys and Beamish
,less bitter than the Dubliner , were a bit more friendly/easy going in the far south also
Now back to the topic at hand , Scotland goes to the polls soon , she may well be on the road out of the union by the looks ,