Actually Mike Rutherford was never really the singer in Mike and The Mechanics, He was the writer and guitarist. Paul Carrack and the Late Paul Young (different one), were the main singers, It was also written with BA Robertson. Most of the Lyrics came from him as like mike he too had lost his father at the time.
I didn't know BA Robertson wrote it!! I just read on Wiki that "The Mike + The Mechanics version was initially promoted to give the impression about the disagreements between Rutherford and his father, who had recently died.
" That's why I'd always assumed it was about Mike's father. A moving song no matter who it was about though.