Hehehe. Rank. What a stinkin' subject. The current dan system everybody talks about was invented by Kano Jigoro, and I think it was his worst mistake. It's gone from a tool for judging respective skill levels in a dojo, to a moneymaking commodity for commercial dojos.
I go wherever they'll let me in the door to train, and I wear what they tell me. In aikido I have no rank whatsoever, and I've worn everything thing from dogi and white belt to hakama with black belt. It doesn't mean a thing. Anyone who's trained for 4+ years and can't tell your relative skill level from seeing you move a little needs to go back to remedial basics.
I do a bunch of stuff that doesn't have rank. Probably less than 1% of koryu issue any kind of dan rank. I've been doing Shinto Muso Ryu for years and I still don't have any rank. It'll be years before I manage some, and even than the first one is just a certificate saying that I've started learning the okuden. The only other ranks in Shinto Muso Ryu are teaching certificates. Either you're licensed to teach something, or you're not. It's very simple.
Dan rank is pretty much useless as far as I'm concerned. I'm a judoka, and the only rank certificate I'm interested in is the one you write on the mat with me. If you're better than I am, I want to learn what you know. If I'm better than you, I expect you to want whatever I can give you. I've got rank certificates in 3 different arts, and the only one I'll really value is the one Kiyama Sensei may someday write out saying I know all the Shinto Hatakage Ryu.
If I go somewhere and they say I'm a white belt in their dojo, I'm a white belt in their dojo. The color of the rag holding my dogi shut doesn't change the level of my ability. If they say I'm a black belt in their dojo, I'm a black belt in their dojo. Still doesn't change the level of my skill. If they say that I'm camouflage with red, white, and blue strips in their dojo, I'm running for the door, but it still doesn't change my real skills.
Quite honestly, I find the whole rank issue pretty rank. It impossible to determine what any dan rank represents unless you are familiar with the particular organization that issued it. In US judo alone, there are 3 different bodies authorized to award rank by the International Judo Federation, and they each have their own, extremely different rank requirements for everything from the techniques required to the time in grade. The situation is even worse in Aikido, where there are multiple international organizations, and even within the same national organization it's possible to have multiple, wildly differing, rank requirements depending upon which region you are affiliated with. In things like iaido and tae kwon do, it gets even worse, with a multitude of international, national, and small regional organizations offering ranks in the same arts.
By the time you get done explaining what your rank means in your organization, you may as well not even bother with it. Just tell people who you are and what you've done. Then they can train with you and make the judgement that really counts; the one based on how you perform on the mat.
I'll continue travelling and visiting any dojo that will let me in the door. I just don't worry about what my rank is. I tell people how long I've been training and in what. If they ask I'll tell them where I trained and with who, and yes, I will admit to holding a few dan ranks. But only if they ask.
My dan ranks became pretty much worthless outside of the organizations that issued them the day some other organization started selling ranks, and a few commercial dojos started signing contracts guaranteeing you receive a black belt after 36 months. In the past, a dan rank didn't mean you made all the payments on your installment plan on time.
Rank, schmank. I wish everyone would just go back to training, and maybe issue a certificate when people are ready to teach. Everything else is just a way of paying for the organization's bills.