Don J. Modesto wrote:
FWIW, Peter, your descriptions of KOTE GAESHI (online) and IKKYO (across the breakfast table) helped me a lot. I'd love to hear you describe IKKYO ala Yamaguchi. Taking Gleason's IKKYO was quite illuminating.
When I trained in the UK, the way I originally learned Shoumen uchi ikkyou ura was the way illustrated in, e.g., Saito's "Aikido: Its Heart and Appearance", pp. 64-65, or in Shioda's "Total Aikido", p.86-87 (there is no illustration in the earlier book "Dynamic Aikido"). Note especially the alignment of the feet and the trajectory of uke's elbow. The problem with this approach is that there is a temptation for a non-expert to block uke's attack sideways and thus to deflect the attack over the centre line in the opposite direction from the eventual tenkan movement (i.e., if the attack requires you to do a left tenkan movement, the deflection would be to your right).
With Yamaguchi Sensei the initial foot alignment was quite different and the much deeper initial irimi allowed tori to control uke's elbow without blocking uke's movement at all. Thus, if uke's initial attack, with the right hand, required a left irimi/tenkan movement, tori's left elbow would be touching the small of uke's back, as the tenkan spiral was executed.
Edit: The difference in the foot alignment is very difficult even to see, if you have been brought up to do the technique in 'textbook' form. It took me quite some time to see the differences and so I never teach both forms in one class (as I did at Aiki Expo 2002).