You will never be as good shooting cross dominate as you will be if you take the time to shoot with your normal dominate eye. We used to force the guys to shoot with thier dominate eye and it worked very well. After the initial "I don't want to", they found themselves to be more comfortable and relaxed shooting.
I would recommend that he stops shooting right handed with left eye and train for just a bit left handed and left eyed. I think his ability will go up after the initial shock is over with and he learns to relax shooting with his left hand. He will learn to point more naturally with the left hand and during barrier shooting he willnot have to expose half of his body on both sides of the body due to his crossing of slhooting left eye, but right handed. remember he is left eyed due to the fact that his right hemisphere is dominate, crossing it will cause some problems beyond his shooting during move and shoot time.
My thoughts and his decision. Let the fun begin!
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Hold Hard guys
Rick B.
Knowledge is knowing a tomato is a fruit.
Wisdom is knowing it is great on a hamburger but not so great sticking one up your ass.
Author - Richard.
Experience is what you get right after you need it.
Author unknown.