Looking at you hands

When i first started Tiaji quan, they always say that where the eye looks is importand and it can either make your break your routine. At first i thought it would be good if i get my body postures and alignment right first, then i would go on to do my eye coordination. Well, that's what i did!
However, half way through getting my postures and alignment correct, I started to realise the use of the eyes.
The eyes actually help in getting the postures and body alignments correct! At the same time, it helps you to watch where your attack is going to land and helps you to focus your energy.
By always keeping your hands in sight, you can sometimes observe the movements of your hands to every last turn or twist and can thus improve your routine. One of my teacher says it can even be used to improve your eyesight!!!I don't know if that is true though...
However after learning taiji, i realise that i can respond markedly better to catch things that drops accidently. I wonder if it the result of better hand eye coordination.