Make organizational decisions?
I for one don't associate absolute or even relative martial skill with dan ranks at all. I've seen too many lower ranked black belts who can run circles around their seniors.
I hope you don't mean technical. You can't compare a 3rd-5th dan - around 25-30years old, to 8th and above...... 50 years old.
That and well, there's a tendency for seniors to teach and not train, I know some of the senior senseis I've trained with have lost some serious skill because of lack of training. i.e. they become masters at teaching the art.