Re: Standards of testing???
I think it is a mistake to identify "unity" with "everyone has to be the same."
I train regularly at one dojo and semi-regularly at another. There is a very important aikido unity here--both dojo recognize me as a student of aikido and do not hassle me over the cross-training or waste their energy in "who is better?" struggles. But there is no unity of testing requirements, nor could there be as one dojo bans techniques which the other considers integral to their style. The ukemi are also startlingly different.
If they were somehow forced to teach the same style, what good would it do me to have two of them? I love this situation precisely because it is so full of differences and surprises, so my mind is kept agile (and frequently boggled). Also, I strongly believe that for each dojo, there are advances in the art which they would be more likely to find than the other, because of their different style and philosophy. Force them together and you would tend to end up with fewer innovations.
I think that something forced to be homogeneous is probably also going to be forced to be static, unchanging. It's really hard to make changes if they have to be accepted by every aikido school in the world, all at once. It's much easier if some schools can experiment with new material, see how it works, and then convince (or not) other schools--the way it seems to be happening with different styles of ukemi within Aikikai in the United States right now. If uniformity were enforced, either no one could use the new-style ukemi, or everyone would have to; in either case we would have a lot less chance to judge whether they are helpful, much less to decide that they help some people and not others.
And if aikido cannot change or grow, I think it will die off. Why participate in an art where you can only copy what someone else has already done, and never find anything new?
If you really, really need to know if your aikido is more valid than someone else's, you can fight with them. It's not very aiki but sometimes it's the most satisfactory answer to this question. Trying to get a rank-granting organization to settle the fight for you is just going to be an exercise in frustration, and doesn't really do anything to change the basic motivation--it's still "I want to prove mine is better than theirs." It doesn't become any more aiki by being done by a ranking association rather than you personally.
(I have a streak of this in my temperment. So far my experience is that no matter where I visit, if someone is ranked much above me he or she can wipe the mat with me. Occasionally I can excel at specific tricky things which my home dojo emphasizes, but I have never hassled a senior student without being quickly shown that they are, indeed, senior.)