That's cool but it sounds like this tool is way oversold. It namedrops DFW and other great authors then shows examples of it correcting spacing and "brb." This isn't stylistic revising that takes you closer to those writers, it's just simple corrections.
But still, it corrects incorrect things that my spell checker doesn't see, like inconsistent spacing and 'goofy approximations' like (R) for ®. (Depends on your definition of incorrect, but I personally would not mind at all if these things were homogenized for everyone, it would not take any richness out of the English language).
What I'd like (--help doesn't list such an option) would be to be able to enable some checks with a flag while disabling other parts (the ones that contain suggestions you can elect to break).