I quite like the idea as a conceptual software art work.
If they’re being entirely serious with this then of course it’s a silly idea which will neither work as intended nor improve people’s writing; only the most prescriptive or hyper-specific pieces of advice can be expressed in regexp form, and Word’s grammar checker already does some of that kind of stuff (e.g. its hatred of the passive voice, which causes academic writing to be a sea of green underlining).
But what I like is the idea that (assuming its rules are easy to program) online forms could react to your writing in domain-specific ways. For example, if someone types “evolution is just a theory”, the comment widget could respond to their problems before they even click “send”.
