Ha, that's just great. I should've known some amazing keyfu nerd already worked it out ;) Thank you for the convincing demo!
I guess the lowest count is 2 (or 1 with a timer), but what is the practical character limit, where speed/ease is compromised? Or in other words, are there a 'sweetspot' for number of keys on a keyboard ?
that's a good question. if one is willing to completely relearn a different input method then the sweet spot is probably stenotype which is around 24 keys and professionals boast 200-300 wpm speeds. But that is impractically hard to learn if you really don't need to type that fast. I used to be able to get 20wpm typing on this keyboard, and i've seen someone hit 60 (by incorporating the supported whole word chords), so it's more usable than you might think. if you ask Ben Vallack, then 16 keys is pretty optimal. My sweetspot has been 34 with the Sweep personally.