Arguments could be made that it's inefficient or un-ergonomic, though I'm doubtful how much difference it makes on a modern keyboard. There's an oft-repeated story about the qwerty layout being designed to keep people from typing fast enough to jam typewriters. I can't speak to the legitimacy of the story, but I do collect typewriters and I can say for sure that there's a lot more pressure and key travel (and time!) required to slam a type bar into the ribbon than is needed to press a modern keyboard key.
I learned Dvorak a decade ago and loved it unless someone else had to use my computer or I had to use a shared computer. I'm typing this on a qwerty keyboard and I'm okay with that now.
> There's an oft-repeated story about the qwerty layout being designed to keep people from typing fast enough to jam typewriters.
Typewriter layouts are designed to avoid jamming, but not by reducing typing speed. They place letters that are pressed in direct succession apart, so that the levers don’t collide. Trained typists can write pretty damn fast on a typewriter.
I thought I remembered something about that, thanks. Dvorak does seem to cluster a lot of commonly used letters, which would definitely jam neighboring type bars pretty quickly unless they used a Blickensderfer-[1] or Selectric-style unified type element.
I've always wanted a Blick, their "scientific" DHIATENSOR layout intrigues me. They also made a qwerty version and I seem to remember a story that their salespeople would make you sign a waiver that you were choosing a less efficient keyboard if you bought one. That's certainly 90% marketing for their layout and maybe 10% fact, but I find it amusing (if true, but I can't seem to find a reference to it any more).
I'll bet typewriter-trained typists can really move. It's definitely a separate skill, at least for the manual typewriters in my collection which have about an inch of key travel and a heck of a lot more actuation force than the gateron red switches I use at work. :-)
Ultimately I find that the fastest layout is the one you know.
> They place letters that are pressed in direct succession apart,
... and that really reduces typing speed. When i switched to dworak I was amazed how my fingers just roll on a keyboard, forming sentences faster than I even form a conscious understanding in which succession should I move my fingers. It just happens as if by itself!! Just think of a word to type and it is already on the screen.
That may be the effect for you, but it's not a goal. It's maybe a tradeoff, but machine writing is a trainable craft. Usual results for trained people are at about 200 - 400 characters per minute measured over 10 minutes. Championship results are at up to 900 characters.
There are plenty of unofficial records and leader boards for typing speeds where qwerty typists are just as capable (more so even due to sheer availability) as Dvorak typists at hitting 200+wpm, and while that alone shouldn't be used to judge the quality of a particular layout it shouldn't be ignored that there's no difference in attainable max speeds done in short bursts. That says nothing about sustained typing of course, but I strongly suspect if you're already a competent and fast typist in qwerty you'll be comparably as fast in Dvorak and vice versa.
Dvorak is actually pretty bad as a smartphone keyboard, it's advantages with two-handed typing on real keyboard become disadvantages if you type with your thumb.
Dvorak has specialised right- and left-handed layouts. Maybe it also needs specialised one finger layouts, too.
I had wondered about phone keyboards. Part of the reason I switched back was that I couldn't change the layout on my phone and got tired of switching back and forth. (I know there are probably some options now, but there weren't on iPhone 4, Kindle touch, or feature phones with physical keyboards.)
I can imagine you'd need to use both thumbs extensively or you'd be jumping back and forth. I definitely found that when I was laying on my side on the couch, propped up with one arm, qwerty was easier to use with one hand. Not that that's an ergonomic or sustainable way to type, but I was a lazy college student and I didn't care.
I learned Dvorak a decade ago and loved it unless someone else had to use my computer or I had to use a shared computer. I'm typing this on a qwerty keyboard and I'm okay with that now.