What WAS my favourite course and why?
You asked the question in the past tense. It used to be Royal County Down, but I rather suspect that it would take me apart these days. The situation is incomparable, the imposing dunes, those whiskery bunkers, narrow strips of undulating fairway of wonderful crisp turf, holes of all kinds and invention - so many magical qualities.
Much of the same could be said of The Old Course, although it suffers from the eye-sore of the Old Course Hotel. Again, I haven't played it for some years, and when my wife and I walked round the course last summer I was glad I was not playing because the play was SO slow. Unlike RCD, TOC allows a very average player such as I to get round reasonably unscathed, and very possibly with the same ball I began with.
Of the inland courses Ganton gets my nod, as much for its wonderful atmosphere as its great course. Perhaps it is the fact that I have usually played well at Ganton (better not go back!) that puts it in my mind ahead of Sunningdale or Woodhall Spa, neither of which I have ever played well.