Learning new keys
Learning new keys
It is not so much about relative distance to the home position. The more important measure is if there are lots of bigrams to be pressed by the middle finger on the same hand – it is believed that a lateral stretch, meaning having to press a key on the central index columns, right next to another key on the same hand middle finger column (e.g., a qwerty ‘gd’), is more uncomfortable than if the index key is on the home column (a qwerty ‘vd’). This is the logic behind the dh mod.
Personally I think both ‘d’ and ‘h’ are of too high a frequency to be placed on the index finger non-home position, so neither the vanilla nor the dh variant of colemak is good in that regard.
d is the 11th most frequent letter [1], so there are many other letters vying for the 8 main home row positions. However h is 9th, it’s a good candidate for a better position, since it occurs in the two most frequent bigrams (th and he).
Since backspace is used far less than frequent letters by competent typists and enter is also relatively infrequent, it is probably best to put something like e on the thumb cluster, so that h can be on the home row.
For me it doesn’t matter much. Since I have a contoured keyboard nearly all alpha keys are easy to reach with my hand on the palm rest (not hovering). But I’d rather have h on the home row as well, since it reduces finger movement for frequent bigrams like th. I have backspace on one of my thumb keys, but I don’t use it frequently, to it’d be more optimal to put a letter like e there, so that h can move to the home row. So even though I use Colemak-DH, I am experimenting a bit with other layouts like Maltron since I don’t believe Colemak it necessary among the best layouts, it just gained quite a lot of popularity. Well and it’s fun to rewire parts of your brain :).
It’s a bit of a shame that layouts are high effort. Given a large enough budget, you can try multiple ergo keyboards. But the cost of learning a layout is so high that people experiment only little with it (if at all), so people continue to use QWERTY or if they learn something else it would be Colemak now or Dvorak 20 years ago. Of course Colemak and Dvorak are large improvements over QWERTY, but they may also be local optima.