You know, it's interesting that Ueshiba flipped the roles of uchidachi and shidachi in ichi-no-tachi.
You mean how the Aikiken kata begins with the kata "winner" / nage advancing on the kata "loser" / uke? But in the Kashima kata, it's the kata "loser" / shidachi who advances.
In every real
sword system I have seen, uchidachi and shidachi start five steps away, and the kata begins with that space being closed somehow. There is a lot going on in those three to five steps before contact. (Is there a generic technical term for the coming together part of a kumitachi?)
Aikiken doesn't seem to have that. I don't see it in these videos. In Saotome Sensei's kata, uke and nage start in seigan with kissaki touching. (Is there a generic technical term for the distance at which two swordsmen in seigan can touch the tips of their swords together?) I've always been curious why O Sensei / Kissomaru / Saito didn't think it was worthwhile to include that.