I know you were probably joking. But in my playing days, my right-handed swing was so messed up that a guy suggested to me that I should practice batting left-handed. The premise being that you would have to take it back to your basic swing to generate any bat speed. I swung the bat 50 times from each side a day until I got more and more comfortable swinging left-handed. I never took it to a game because my power was still from the right side but would fool around with it in batting practice. I actually started making cleaner contact left-handed than right-handed. To the point that guys would ask me if I was naturally a left-handed hitter.
The point being is that it actually did help me with my dominant side. But I think it was more to do with taking my swing back to a basic swing. Short and simple.
