If you don't want the details and just want to head directly to the conclusion scroll down to the bottom of the page.
How different it is to type on Dvorak vs. QWERTY?
(What follows is based on my experience and opinions only; do not consider this to be an extensive study of layout differences. In any case these remarks are about subtle differences, only those that have used both for a long time can really feel it).
Since QWERTY forces the typist to change rows more often, the typist typically has his hands a little bit further away from the keyboard in order to reach the entire keyboard faster without having to twist his/her hands in all directions. The movements of the hands happen in the wrist rather than the fingers. On a Dvorak layout, the typist has typically his/her hands practically sitting on the keyboard all the time and most of the movement happens on the fingers. It becomes very obvious (and almost annoying) that some keys require a wrist movement. On a typewriter the wrist movement was necessary anyway and this only confirms how good the design of QWERTY was for it's purpose.
The Simplified Dvorak layout is optimised for speed and comfort but you will notice comfort first, before acquiring speed. There are people that can type much faster on QWERTY than I will ever be able to type on Dvorak. I can touch type on QWERTY about 50 words per minute and that's fine for me. Just for comparison, the fastest typists in the world have averages ranging from 150wpm to 250wpm. The official Guinness record (2005) of typing speed and endurance was achieved on a Dvorak layout by Barbara Blackburn maintaining 150wpm for a period of 50 minutes. If you are an average typist like me, you will never reach these extraordinary speeds, no matter what layout you have. Nevertheless you will feel that the keys are right under your fingers when you need them. The comfort of Dvorak is it's best feature and this translates not only in an increased pleasure of typing but it can also reduce RSI (Repetitive Strain Injury). Some doctors recommend the Dvorak layout for patients suffering from RSI.
Switching to Dvorak simplified layout (day by day)
I've decided to give Dvorak a try and see for myself how good (or not) it is. There's nothing to say about the theory behind it but, in the real world, how hard is it to make the transition and what benefits does it bring?
Day one: the first day is by far the hardest. I haven't changed my keyboard hardware in any way, only the layout is different, so the keys that I press do not correspond to the output on my screen. As you can imagine, I can't type anything at all without looking up the letters on a keyboard image that I have printed on paper. It can take ages to write a single sentence since I can't just look down at my keyboard to find the letters I need. This is actually good to loose the habit of looking at the keyboard (even when you know where the key is located) but it is definitely a patience game. So I decided to dedicate the first day just to learn by heart all the letters on the keyboard using a typing tutor software called Klavaro. It took me a couple of hours but it worked. Although it might take several seconds (sometimes even more) to remember the letter position, I learned them all in day one. This is the first thing to do, otherwise I wouldn't have gotten anywhere. It is also possible to change the letters physically, it takes about half an hour and there are plenty of tutorials online on how to remove and reposition the keys. I ended up doing this a few days later to help those that eventually need to type something on my computer.
Day two: after a good night of sleep things are already a bit better. I can type without looking on a keyboard image although I still feel the need to have a cheat sheet around when I get stuck. Of course, I still type very slowly at no more than one letter per second at the very best. I still did a few exercises in Klavaro in an attempt to accelerate my learning pace but I felt that I should do more interesting things like writing e-mails, chat or search the web. It was useless to try to work with the modified layout since the typing alone was requiring too much attention and concentration. I just had to switch back to QWERTY in order to actually get my things done. Some people say it's better to stick with it once and for all but I had to switch back and it was ok for me.
Day three: on day three I started using Dvorak without looking at any visual aid. It took time to remember some letters but I decided to avoid visual aids. I stumbled upon some annoying things like the inconvenient short-cuts Ctrl+C, Ctrl+V that are now located on random places across my keyboard (you can use Ctrl+Insert and Shift+Insert instead) and special characters like brackets and dash/underline that forced me to reach for my cheat sheet again. After some time I got used to the new position of shortcuts but it is an issue at the beginning. Typing passwords were also tricky since I couldn't see the output and had to type very carefully. On the other hand I could see that the majority of the letters I used were indeed located on the “home” row (the one on the middle) and I spent most of the time with my fingers at rest on the same keys instead of jumping around like I did with QWERTY. The comma and full stop at the top pleased me and improved the comfort of typing.
Rest of the week: the steep learning curve started getting more gentle around day four. I could do most things that I needed, even though it took me more time than usual. The frustration of the first days were over and things were getting more automatic. Strangely enough, as I began to type faster I noticed that I would often make mistakes that were either from my QWERTY habits or from switching left and right respecting the Dvorak layout. This is just to mention that typing still required concentration. The improvements from one day to the next were not as radical as during the first days and that also annoyed me. I was willing to get at it faster. Doing exercises on Klavaro was still the best way to improve my speed without going crazy. At the end of the first week I was typing roughly 15-20 words per minute with a good accuracy, not half of the speed I could type on QWERTY.
Week two: it's only after two weeks or so that I began to feel comfortable with Dvorak. Although my writing speed was still clearly inferior to my usual QWERTY speed, it's only after a fortnight that typing didn't require so much concentration. Only a few common words were really getting automatic and didn't require any effort at all. On my exercises my speed was only at 25 WPM but the fluidity and accuracy improved a lot. I was able to work and do my usual thing just as I did with QWERTY, only a little bit slower.
First month: At the end of the first month, finally, the switch to Dvorak started to pay off. Not only my speed was acceptable (above 30wpm) but the comfort of typing was very pleasant. I still couldn't type as fast as I did with QWERTY (about 50wpm) but one has to consider that it took me several years to acquire my QWERTY speed. I certainly did not type 30wpm on QWERTY one month after learning to touch type.
After a year: After a year or so Dvorak became, of course, very natural to me. My writing speed and accuracy were roughly the same as with QWERTY (although, by the time, I had forgotten how to touch type on a QWERTY keyboard). Even at this stage, using Dvorak required some extra effort but only because my computer was different from everybody else's. Using Dvorak felt a little bit like being a freak, Dvorak forced me to adapt back and forth between my personal stuff and the rest of the world.
After two years: After a lot of different situations, came an occasion where typing fast on a QWERTY keyboard became rather important. You can't always force your choices on others so at this point I decided to switch back to QWERTY only to be adapted to the world I live in.
Dvorak layout is great. If I could change the course of history I would definitely make it the standard layout. Since I can do little to change the course of history in that respect, I accept the adoption of QWERTY as a historical legacy. After only one month of training I realised how the initial effort involved in switching is big and only starts compensating after a long time. After two years I realised that having a standard is much more important than having the best alternative. In my humble opinion, QWERTY is good enough and Dvorak improvements are rather small (not enough to make it worth it at this point in history).
Keep in mind also that you will never write faster than you can think, of course, and often the bottleneck is in your head rather than on your fingers.
In any case, it you want to try it out, here's my advice for a smooth transition:
1 – Learn the keys using some typing tutor software
2 – Do some more exercises everyday with your typing tutor
3 – If you don't feel yet comfortable, keep doing exercises
That's about it. It's much better to get tired doing exercises rather than doing actual work! Once you do the transition you will fully understand the reasons why some standards remain while their optimised alternatives have a hard time to flourish!
Interactive Keyboard analyzer
Dvorak simplified layout (Wikipedia)
Keyboard layouts (Wikipedia)
Letter frequency (Wikipedia)