A few years back we changed timing feedback so that Good is wider, so it includes some concept of both 'good early' and 'good late' (this depends on pitch location - on an away pitch being slightly late is fine). Unfortunately there isn't a good way to show both meanings of timing: a) your timing was good for that pitch location, b) the exact early/late/direction of your timing more precisely. We've experimented but simple beats out the other versions we tried.
Essentially, the direction of the hit off the bat will tell you the more precise early/late timing you had, after factoring in location. The swing analysis timing field tells you something more that isn't as obvious.