Mike
This is an excellent technique as you never forget your patch of tape on a days shooting! I have seen people sticking their left thumb up to blank the foresight. You used to be able to get little screens to attach to the gun to achieve the same result. I suppose the modern equivalent are the foresights with small tubes to the rear which prevent the left eye seeing the bead.
I would guess that the benefits to you are even greater on left to right crossers as this is when right handed shooter usually get the most problems. Even right handed people with fairly dominant right eyes can experience the left eye taking over on left to right crossers.
While opinion is divided over closing of blanking an eye I am happy for individuals to do it on crossers if it improves their score. Whatever advice we give in shooting is usually a compromise of some sort. The objective is to get the best result an individual is capable of - by whatever means.
I have never advised any of my students to shoot with both eyes closed - they seem quite capable of doing that for themselves!!
John
