Re: significance to testing/belt rank?
I came back to edit but too late...
I also saw a lot come and go without ever testing and some were there for a long time.
In another Karate class with the same kind of standards we had 2 guys start the same time. They didn;t know each other before just started the same day. They were both "green belts" about 5th kyu when one started talking about how is friend who started around the same time was a black belt already. Sensei just told him to go to that school then - which he did. He came back 6 months later wearing a black belt while his old class-mate was still wearing green. So Sensei had them spar. Needles to say, the new black belt got creamed (actually knocked out).
I'm sure there are a lot of dojo where there are stories like this. It just goes to show that rank means nothing.