I was trying to us the Canary as a diagnosis tool figuring what was online and what was off but I couldn't make sense of how to use it. There was a bug where we default to regionserver 'mode' always and only way to change it was via a system property and a cryptic class name.
Changed it so we don't specify output ahead of figuring what 'mode' we are to run in. Cleaned-up usage and added commentary. It seems useable now (Did not change command-line args though they need changing).