It is true that if you can get him to look in the direction you want hi thought to be , it will help. But it's only part of the whole, and if you spend your time and focus trying to make your judegements on what to do next based on being able to see the eyes, you will be late more often than not, and as timing is everything, it's more important to be open to the whole picture.
Have you ever read Sally Swift's book "Centered Riding"? She talks about using "soft eyes" in riding; where you do not really have a narrow focus on what is in front of you but rather allow your periferal vision to be a part of your conscious brain, too.
I think your approach to viewing the whole body language is more accurate.
However, I will say that sometimes a horse will move the direction you are pulling him, either with a rein or a leadline, but his thought will be somewhere else and this will be evident because as his eye is rolled away from you, you will be able to see the white of the eye. When you get a horse to move with out his thought really being in the movement, YOU are moving him, not getting him to comply and move HIMSELF. If he does it himself, with his thought in the movement, he will remember that much better and it will be easier to get that movement from him the next time you ask.
Last edited by tinyliny; 08-16-2013 at 01:18 PM.