I dunno, not having to move your fingers from their positions seems like a big advantage even if you can't get the full X00 wpm an expert can get in regular text.

I agree that reduced finger movement is a crucial step in achieving typing efficiency. This is nicely solved by mod tap modifiers in QMK/ZMK[1] where key acts as a char when tapped and as a layer while pressed.

[1]: https://github.com/qmk/qmk_firmware/blob/master/docs/mod_tap...