The late director Stanley Kubrick (2001:A Space Odyssey) used to say that if you can turn off the sound and still follow the story, you've made a film, but if you can still follow the story with only the sound, you haven't.
Instead of film, however, let's insert video game.
Logic dictates that if there is more than one solution, then the problem is not conclusive.
Just because Crono never talks doesn't mean he's a mute. Case in point? Penn & Teller.
Hopefully, this will put an end to the the Straw Man Arguments out there.