Similarity to QWERTY is very important in the learning stage in order to make learning easier and faster. Once you master a new keyboard layout, you'll often start to forget how to type in QWERTY. People who have been typing in Dvorak for a long time and need to use QWERTY for one reason or another find themselves almost unable to type. If for example, you move the Shift keys, it would be much more difficult to adjust from ToB keyboard to a normal laptop keyboard, for example.
It's a QWERTY world after all. I used Dvorak for two years before I gave up on it. I had to use QWERTY some of the time, and switching between layouts was very error prone and difficult. I find it much easier to switch back and forth between Colemak and QWERTY because it's much easier to hunt keys when I'm typing on Colemak.
Perhaps part of what makes it more difficult to switch between Dvorak and Qwerty is that Dvorak is very asymmetric. Once your brain has adapted to the left hand doing all the vowels and that about the only thing can be done in rolls are diphtongs and consonant clusters, it's harder to go back to Qwerty. But I don't know.
For me, personally, the easiest changes to learn are 1. moving the keys up or down 2. mirroring them to the excact opposite posititon 3. swapping similiar letters, like P and B. The hardest are those that move keys from the stronger two fingers to the weaker ones and to make it even worse, flip hands while doing it. And by hardest I mean those that I find it disgusting to accommodate to my nervous system, not the ones that are take the longest to hunt or whatever.
But I'm not that familiar with the long term effects on maintaining “fluency” on multiple layouts. If you must move some keys, is it better to just try move them close to the original positions, or away from them, to avoid mix-ups? Then what again is close, and are there some kinds of changes, despite being easy to learn, that would melt down in your mind over time and often cause mix-ups? Like that Dvorak Y and T thing you mentioned.
If languages are to trust, learning another, similiar language would be easy as long as you're fluent with the first one. Also at first the hardest to memorize would be words, but in the long run what would take the most effort would be learning the structures, sentence formation and all the other more abstract aspects of thought that drive the upper, actual levels of speech. Interference is also so much more common in these deeper areas where it is often hard to draw excact lines between the two languages.
Is there a point to make out of this all? Even though it would take time to learn a thing at first, it may only mean that it's this simple “upper level” detail which won't bother you much in future. The most difficult to get used to are changes at the deepest, possibly even invisible levels where even small alterations can cause complete structural collapses. But which are the smallest detail-like aspects in layout memorizing and which the deeper ones which we rather just leave to intuition, that I would like to know…
Punctuation keys are ridiculously easy to learn anyway, even though they do require a bit getting used to, and I can go back to the Qwerty way with no problems.
You perform the finger balance calculation as if 'X' position is as easy to press as the 'S' position. Again, you shouldn't put the letter 'D' on the 'W' position.
You're correct, the keys should be weighed differently in the finger balance percentages. I still fail to see the problem with the D position though, but it is probably just me then. I have put keys like M, F, P or G there in recent versions as a compromise.
I however find the the Qwerty U position, where you have L, to be even worse than Qwerty W. Pressing it almost always requires a long stretch of the index finger and forces the other fingers to be turned a bit outwards as well. After it pressing other keys with the same hand is quite uncomfortable. It also makes the index fingers roll around the center a lot more than would be necessary, resulting in an increasing actual finger distance. Placing uncommon characters on the top row would greatly reduce index finger stress and distance…This was one of the reasons I started modifying Colemak in the first place.
Same finger is definitely a bad thing, especially with the weak fingers. e.g. try to press QZQZQZ and see how tiring it is. When typing in high speeds (>80WPM), same finger becomes one of the most important factors for speed, and combos/rolls become much less significant. Every time you have to hit a same-finger, it slows you down and interrupts your typing stream. I really don't think I'm overstating the importance of same-finger, it really is very important as it affects typing fluency, speed, accuracy, and strain. Words such as "wryly" require pressing 5 times with the same finger.
There are certain bad combos which slow down typing almost as much as same-fingers. Try something like RAT vs RTD on Colemak. Those should also be eliminated, the roll direction should be kept towards the center, Qwerty positions should be respscted, combos and hand alteration should be optimized; scores under 2.0 are impossible without sacrificing anything.
Moreover, designing for low same-finger doesn't have to conflict with any other design principle. Colemak, Capewell, Klausler's, Maltron, Arensito all achieve very low same-finger. Arensito is also designed for maximum combos like ToB, so there's no excuse to design a modern keyboard layout with such high same-finger ratio.
-Colemak is an almost Dvorak-like layout which almost never keeps the fingers in a flowing motion and is far from symmetric
-Capewell (close) and Maltron are not Qwerty-like layouts, have a bad finger balance and as far as I know have more bad combos
-Arensito is designed for ergonomic keyboards with even rows (it places three keys on ring and middle fingers), which makes layout designing a lot easier, and it isn't Qwerty-based
- The fact that Klausler couldn't find a layout better than Dvorak already shows that we should completely disregard him
The pinkies work too hard, the pinkies do too much same-finger
If the apostrophe thing is let aside, the only difference in pinkie usage between our layouts, is that in ToB the comma is added on the left pinkie. The right one still has more stress, if shift presses are not counted anyway. Maybe you just found it hard to get used to the new location of the punctuation and felt it as strain at first… The way comma and dot are pressed should put more strain on the wrists more than on the fingers, so once you get used to it, it shouldn't stress the pinkies as much. I will change the punctuation back to normal though if others report strain as well.
same-hand jumping combos such as "BU" cause strain, large distance same-finger combos such "BY" are difficult to type
Since B is about as close to both hands, it is supposed to be altered between them depending on the following / previous keys. This is something I learned to do on Qwerty anyway. This should solve the issue of uncomfortable stretches and same-finger typing involving it. Moreover, Y can be pressed with the middle finger to avoid same-finger typing, much the same way you'd likely type GR on Qwerty.
I miss O on the home position, D is uncomfortable to type. Typing 'the' is nice, but I don't think it's worth all the other sacrifices you made in the layout.
I think I'll have to move the O down in future versions, which will probably make my layout more like Arensito or Capewell. Only better. :P I'll also stop making compromises for the other languages. I've got the alternatives pretty much thought out already, even though I have to read something about how the memory works before moving further… But even before that, I'll take a little break from keyboard designing, spend more time with my friends and fulfill all my other New Year's promises (here we actually make promises instead of wishes), finish Twilight Princess and the list goes on… But I'll be back anyway to kick all your other designer asses and actually release the layout someday.
Finally, I like the first version better, but here's my current one anyway: (less same-finger, much more bad combos)
,GUPWJKYH.
ASITDRNELO
ZXCVBFM:Q
Happy New Year to everyone and congratulations to Shai for winning. ^_^