Another sovereign property of Irn Bru is its usefulness as a mixer. Although it lacks the subtlety to complement and enhance good spirits, it neatly masks the nasty artificial flavours of cheap gin or vodka with rather nice artificial flavours of its own.
I'm told that there even exists, north of the border, an alcopop consisting of Irn Bru and Bell's, thereby (explained the Scot telling me this) mixing Scotland's second and third national drinks. If only they could have got Buckfast in...