Re: Is is it still Aikido if you take away the Japanese clothes, etiquette and other things?
I think there is a focus here on the fact that sometimes we train without all the fancy clothes. I'm trying to look at the overall practice, not the occasional times when we do something unusual. What is the baseline? That's dressed in funny clothes. We can train without them, but the overwhelming majority of the time we wear the uniform.
I chuckled when you mentioned Kano Shihan and keikogi. In the circles I run around in in Japan, keikogi means the nice, traditional indigo uwagi worn for kendo, kenjutsu and related stuff. The thing Kano Shihan created is usually referred to particularly as a judogi. It may be because I spend so much time in the koryu world and so little time in gendai budo circles these days.
I do find it interesting that the group consensus falls on the side of etiquette and non-physical cultural aspects are necessary, but the particular clothing is not.