Sorry if I am going over old ground, but I can't be bothered to read 27 pages of anti-Sassenach invective
I was born in Glasgow (Govan - it is like Fallujah, but without the sunshine and friendly people), joined the RAF, and then settled down in Yorkshire (with some time abroad in Europe and NZ).
I have a very simple decision tree
If Scotland are playing, I support Scotland (even against England).
If Scotland aren't playing, I will support England (if they are playing).
If Scotland or England aren't playing, I will support Wales (except against NZ in Rugby Union, as I have spent more time in NZ than in Wales).
As above for NI.
Why do so many Scots feel they have to support two teams - Scotland, and anyone playing against England. We are all part of Great Britain, and the sum of all is greater than the individual parts.
Rant over.