Evidence that practicing spaceograms works?

[quesada]

I'm curious about the idea of practicing spaceograms, and that of not using backspace or highlighing where the errors were. But what do we have to be justified believing leveltype works? I know this is hard, and I'd be content with even annecdotal evience by those using it. In /r/typing only one user seems to have used leveltyping, and then only for 8hr and in combination with monkeytype.

Anyone out there can suggest any evidence?