re: Why are Left Handers used only at 1st Base

Leftys can't catch for 2 reasons-

On a throw down to 2nd on a steal, their arm would be right in line with a right handed batter. The same issue that righty catchers have with lefty batters, but there's obviously far more righty hitters

And the throw down to 3rd on a steal is almost impossible. The time it took to shift your feet and turn your shoulders would stop you from ever throwing anyone out.