The dominant eye is usually the main factor in determining the vision center, whether or not they're aligned together.
pj
chgo
Patrick,
Sorry for being a bit late to the party, but you seem to be making a distinction between eye dominance and vision center that I do not really understand.
The way I think about it, an individual's eye dominance will be on a scale ranging from 100% left eye dominant to 100% right eye dominant. The location of an individual's vision center tells you where you are on that scale. So if your vision center is exactly central, then you would be described as not having an eye dominance. Conversely, if your vision center was directly below your left eye, then you would be described as 100% left eye dominant. etc
Are you defining terms differently or thinking about it in a different way?
[Edit: I think I might be able to answer my own question (but please let me know if you disagree). In short, the vision center is one of a number of ways of defining eye dominance, and is the one most relevant to billiards players.
People referring to eye dominance normally refer to dominance as determined (defined?) by the results of by one of a number of standard tests. The tests will not necessarily all give the same result.
For billiards players, one could include another test, which would be where the eyes are in relation to the shot line when it looks 'most right' (leading to the 'vision center'). This test will not necessarily give the same result as others, but is the one that is most relevant to billiards.
So billiards players should concentrate on the vision center and ignore other measures of eye dominance.]