I also found the horizontal use of the Wiimote hurts my hands.
It's that it's just too much of an angle, and it's not really made for horizontal, more the way you hold a gun.
Can you explain that to me? I am not a regular gun holder. But i remember that the part where you hold the gun is something like 45 or 60 degrees from the part that ejects the bullit. Not 90 degrees or zero degrees. So either you always shoot into the ground, or your Wii game play is rather lousy.
Maybe you hold the gun like all the cool guys do in recent movies, about 90 degrees tilted to the inside, but then you have the same problem shooting too far to the left or the right, or the same result with your Wii gameplay.
BTW, I'm using European degrees, where 360 degrees go into a full circle..