Re: significance to testing/belt rank?
Where were you at the USAF Winter Camp 2000, 2002 and 2003? I was there and people were failed.
Where were you at the USAF Yudansha Seminar in 2006. I was there and people were failed.
Where were you at the seminar in Montreal this year? I heard a few people were failed there.
Failures happen and standards exist. It's not like Yamada Sensei is going to look up your name on AikiWeb and let you know when people failed.
In my eight years of aikido, I've seen people get failed at the dan level and within my own dojo, too. It happens.