I'm a long time Roxy and Ferry fan.  I'm also a sax player.  I'm quite qualified to comment on Andy Mackay's ability on the sax.  He is a rock and classical woodwind player.  He's very good at what he does within those genres.  He is not a jazz or r&b musician, which is the style that Dixon is playing on this video.  David Sanborn played on the original studio version.  He's also exceptional.  Mackay simply cannot play this style of sax.