So...if Morihei Ueshiba trained outside in normal clothing, as he was known to quite often, it wouldn't have been Aikido?
It WAS at one time "normal clothing." It isn't anymore. It's funny: I love costumes, I sew a lot, and I tend to have different clothing for different things - at least for gardening and painting .... but somehow to me the keikogi is NOT intrinsic to the art. Whereas I DO think the bowing and other etiquette does add something to creating a mindset, I really don't think the clothes matter.