Its because of the rules of blind typeing courses that says thumb should be used only for space? If you got such a courses more than a year before and already mastered blind typeing, than stop worrying. Just use thumb for `x`.

> I've tried micro-optimizing special cases like this before, but then I have to think as much about typing as what I'm typing.

It got better with practice. Like blind typeing. All you need is to train you fingers for they do it without conscious effort of thinking. Are you play on some musical instrument? Try it, it teaches how to train your fingers.

It could be different for others. I saw a guy who could do 100 WPM with literally two fingers, although it looked exhausting. A year of waking up with my fingers locked, simultaneously numb and throbbing in pain, taught me that maintaining a relaxed flow is more important than those last 10 WPM. But that means a few combinations like e-x-a will be tap-tap-tap instead of t-t-tap.

things that can't be typed w/o moving your fingers from the home row are really easy to type.

That's why some people (like me) switched to Dvorak.

Your sentence on Qwerty was 43 top, 21 middle and 12 bottom row keypresses.

On Dvorak, it's 24 top, 45 middle and just 7 bottom row characters, twice as good!

"ithout" is also entirely home-row, so you wouldn't need to bother with "w/o". The word demonstrates Dvorak's other feature nicely, hand alternation and outward-to-inwards flow:

  without
  ,gkjsfk (Qwerty equivalent)
  RLRRLLR

But I ran into a few things thay ultimately made me give it up.

Oke was emacs shortcuts — it turns out I mostly don’thave these memorized as letters, but just locations. So then trying to translate from location to querty to colemack was pretty brutal.

The other big problem is you’re instantly less efficient using anyone elses computer.

And a final one was programs that chose shortcuts thoughtfully for qwerty suddenly had really randomly chosen shortcuts.

I do kind of want to give it another shot though....