Well, since an expert typist can do about 150 words per minute with zero errors on a Qwerty keyboard, the argument for using others only applies if you at at that level. Lack of skill is often blamed on the tools. Galbraith developed a better keyboard for Remington so they could beat the world typing record which was something like 250wpm back in the 1920's.
I have never found a picture of the Galbraith layout. Some people say the Dvorak is the same, but I know that is not true because the Dvorak was made so it did not infringe on the Galbraith pattens. I believe the Galbraith was based strickly on letter frequency and hand switching.
The most common typo in typing is probably HTE. Now we all know how to spell THE, but since the H key is so much easier to reach than the T key, our finger hits the T first, thus causing the typo. CH also causes problems. But a skilled typist learns to work the keyboard in spite of those kinds of problems.
My conclusion therefore is that the Querty keyboard is adequate up to 150 words per minute. Also, since that is what you are going to find in almost every English speaking office in the world it is the best one to learn. If you chose to use something else you probably need to carry your own internally mapped keyboard around with you wherever you go. Billions of typists have mastered the Qwerty keyboard, maybe a hundred thousand know some other layout (talking about English language layouts here).
No, despite 50+ years of practice, I do not type anywhere near that level. 35-40wpm clean, transcribing, and maybe 2-2.5 time that, not clean, moving words from my head to the screen. Unlike most reading this I learned to type on a mechanical typewriter, my mother's 1939 Royal portable that she got as a highschool graduation present; boy, was I ever glad to switch to a computer.
