I noticed the same. In my modified version of Twiddler3 I only use thumb for capital letters.
@AlexBravo, did you learn the basic letters first, then expand to MCC?
I did learn basic letters first, but then I wanted a higher speed and fewer finger movements, so I developed what I call "Wearable Input System (WIS)". This system specifies unambiguously how words are typed.
Rule 1:
There should be only one correct way to type something, thus there should be no arguments about how to type something.
The main goal is to allow the development of muscle memory in the fingers for each word.
So typing something without MCCs is somewhat counterproductive, as you learn to type things the wrong way.
MCCs don't just give you a few wpms. They give you very noticeable increase in the speed.
Like 17% increase. So from 45 wpm you get to 53 wpm with MCCs.
MCCs do have a cost of additional cognitive load.
I'll post one day the research I did for myself on MCCs. Here's a small part of it:
For notes.txt:
31 MCCs are used, 2406606 chord are typed to output 2824906 letters.
17% increase in typing speed. Saved chords: 418300 (14%)
Typing 40 wpm with 31 MCCs results in 46 wpm effective typing speed.
61 MCCs are used, 2276097 chord are typed to output 2824906 letters.
24% increase in typing speed. Saved chords: 548809 (19%)
Typing 40 wpm with 61 MCCs results in 49 wpm effective typing speed.
--
For aliceinwonderland.txt:
31 MCCs are used, 130113 chord are typed to output 160028 letters.
22% increase in typing speed. Saved chords: 29915 (18%)
61 MCCs are used, 122302 chord are typed to output 160028 letters.
30% increase in typing speed. Saved chords: 37726 (23%)
Typing with 61 MCCs will increase speed from 40 wpm to 52 wpm.