Hanna Bjork, I agree. Which is why I feel that non-yudansha should be allowed to wear hakama if they feel it is important to them. In other words, it should be up to the individual to chose if they want to wear one or not. The fuss will only be created if yudansha feel upset by this or somehow violated. Afterall, a non-yudansha wearing a hakama isn't really going against the flow or being disrespectful to O-sensei's original wishes.
O-sensei himself said that Aikido begins and ends with formality, so I think that wearing the hakama does help one connect himself with the 7 virtues. Moreover from a practical stand point, from what I understand, the obi and kutshita(sp?) help the wearer feel his hara better. And if one uses the argument that it is simply tradition that yudansha only can wear hakama, then why not just have all classes forego wearing dogi at all? Afterall, it would be cheaper to just wear sweat pants and a tee shirt, not to mention wearing shoes which is more practical.
What concerns me is yudansha who feel it is a privelege or right for only them to be able to wear the hakama. It is their choice of course, and ultimately, I feel that one should respect the wishes of one's instructors. It is rather the principle of the matter, and not the right or privelege that concerns me. The principle being that as with many other formalities, traditions can help us relate to the past and encourage us to follow certain behavioral patterns.