Re: Weapons training leads to good aikido.
"I don't dispute that this is true, however why can't you do this without weapons?"
The answer is because we generally don't do it unless we have weapons . The use of the weapon makes apparent what isn't apparent otherwise. I can show Aikido without words but sometimes, words help. You can teach these things without weapons but most times, they help. I wasn't trained with weapons the first 3 years of my practice but have used them the last 7 years. For me, especially as an instructor, there has been a huge difference in understanding what I should have known and seen with out them. For example, I recently realized that when avoiding a shomenuchi strike with the bokuto using a tenshin, you have to take an extra long step back where as before I tried that with the weapon, I never thought about that. I also realized that the position of the right foot is critical in that you have to place it in such a way as to be able to enter back in when he raises up again. I have incorporated those ideas into my regular body arts since. I must also add that when saying all this, I am refering to the kumi jo and kumi tachi kenjutsu. I never realized anything much from regular bokken tori or jo tori exercises.
As for the form of the technique, the kiri kaeishi exercises so show the form of the technique, they are a wonderful guide to the correct form of the technique. I use them to correct my technique all the time and they serve as excellent illustrations to the students when they unknowingly drift from the form. The hand and foot movemnet of iriminage with the jo show that either you must get behind uke or you must allow him to pass you so you can enter with the hip. I will grant that you don't need the weapon to know or learn that. It's just that using that form as an aid sure helped me to understand that concept. Maybe for those of us that are tactile and visual learners, it makes a difference.