Re: aikido w/o any of the trappings
I think for a beginner it's important to know that the instructor you start to train with has enough experience to teach him/her. We can't judge how good is instructor and if he teaches the right thing if we never practiced before. For this it's necessary to have a proof of eligibility to train. Here where affiliations and ranks have meaning. Even for more advanced student it's sometimes important to be tested. I'm sure it's a very interesting experience and I'm looking forward to it. I think the only advantage of training in dojo is that you have mats that help beginners to learn for example rolls without hurting themselves.
That's my beginner's opinion.