* Maximize the use of 'combos,' i.e., multiple keys hit on the same hand with one comfortable movement
* Minimize the use of uncomfortable combos
* If a key in one of the centre columns is used, have the keys typed before and after the key be typed by the other hand
* Minimize use of awkward positions on the keyboard
I'd also add cadence: it's important to have a nice rhythm when typing normally. This plays into the combos and lack of awkward keys. I suspect that in some ways, it's better to sacrifice a little average speed so long as variance is not very large.
I think minimizing uncomfortable combos is especially important if you happen to use lot of punctuation/symbols etc, eg writing c/c++ code or tinkering around in shell. My local keyboard layout (fi/sv) is absolutely horrible in that respect (see http://en.wikipedia.org/wiki/File:Keyboard_Layout_Swedish.pn...). But we also happen to have two extra letters in our alphabet, so using us-intl is not an option. It would be quite good otherwise, as it just happens that most computer systems seem to be designed to be used with us-intl.
The best solution I have come this far is creating my own custom layout, based on us-intl, but squeezing in those two extra letters. But this approach has one large problem: using any other computer than my home desktop becomes a lot harder. And as I happen to use a lot of other computers, it also hinders me from learning and using my own layout properly.
Also, I have not yet found a reasonable solution to create my own keyboard layouts in Linux, so that it would reliably work all around the system. So my custom layout experimenting has so far been limited to windows only, which is kinda sad.
http://www.michaelcapewell.com/projects/keyboard/index.htm#T...
Roughly quoted:
* Minimize finger movements.
* Maximize the use of 'combos,' i.e., multiple keys hit on the same hand with one comfortable movement
* Minimize the use of uncomfortable combos
* If a key in one of the centre columns is used, have the keys typed before and after the key be typed by the other hand
* Minimize use of awkward positions on the keyboard
I'd also add cadence: it's important to have a nice rhythm when typing normally. This plays into the combos and lack of awkward keys. I suspect that in some ways, it's better to sacrifice a little average speed so long as variance is not very large.