Robbo
Purple Belt
I read that Chuck Norris failed his yellow belt grading so his natural ability must have come through after that. I'm not taking anything away from Chuck but it just demonstrates that maybe natural ability wasn't at play there.
You should read his biography. The test was held in the middle of winter in a dojo with no heat. They had to wait for hours in a seiza (kneeling) waiting for their turn. He seized up and forgot part of a form. They failed him. I'm pretty sure it was for BB though not Yellow, I'll check it and get back.
Rob