Thought I might throw my hat into the ring. There is a lot that I would like to address in this thread however coming in so far down the road I can probably only hit upon bits and pieces.
I have been following this thread [as far as I can understand it] as well as others like it. I feel somewhat compelled to add to the discussion about the Yoshinkan approach to Kihon dosa [basic movements] and other references to the "braced" rear leg.
1st off I would like to note that I think that Mike has hit upon an important observation as to the braced rear leg. I too share his feeling that many are emulating the "finished product" so to speak.
To me it seems that many are replicating only the final aspect for the accumulation and application of "power" that shite uses to generate and then apply in which ever manner to capture uke's center [that of course being the last stage which calls for the extension of the back leg to further shift the weight forward to the front leg].
To hopefully help further the conversation and to perhaps add a "new" angle, I am attaching a few scans from a translation of Yoshinkan Aikido Kiyoyuki Terada sensei's Aikido primer "Zukai Aikido Nyumon" [http://www.seiseikai.org/book.html
The scans are from a translation that was made available when Terada sensei made a visit to London, Ontario back in April 2000. I particularly like this translation because:
1. It is the only one that I know of!
2. It was done by people that where not life long students of Terada sensei and as such reads as a fairly direct translation of his written words.
For the record: Victor Wagner is the copyright holder of this translation.
Also for note: Terada sensei's book is intended to be used as an introduction to Yoshinkan Aikido and as such remains focused on the "basics".
The scans are describing how to do the 6 Kihon dosa movements that comprise all the techniques of Yoshinkan Aikido. All the movements are being described as a two person exercise involving Shite and Uke.
The dosa are:
Elbow power 1 and 2 [Hi Ryoku no Yosei omote and ura]
Body change 1 and 2 [Tai no Henko omote and ura]
Fixing movements 1 and 2 [Shumatsu Dosa omote and ura]
[throughout the book Terada sensei uses the older name variations for many different techniques and sometimes differs from Modern day Yoshinkan honbu].
My immediate question to some here is what purpose do they see uke providing shite in these exercises?
My personal understanding is that shite learns to perform the movements solo with no resistance to learn the correct principles. Uke is added later to reinforce correct lines and principles learned and then add resistance to the training to help facilitate keeping relaxed with correct posture and everything else essential to maintaining correct form for "power" accumulation and application.
In all of these Kihon dosa exercises it seems clear to me that they are teaching one to shift the weight from the back foot to the forward foot [and vise versa] while maintaining posture and not to be in direct conflict with uke's center.
That being said, I don't feel that it means that there is no resistance at all. You have to learn to move uke's center around your own by utilizing correct placement of a myriad of different things. It is probably the biggest deficiency that one can see in how many perform these basic movements. In many peoples inability to correctly manipulate uke's center they resort to bracing and muscling to compensate for the lack of "power' generated from their diluted incorrect movements.
Also, when reference is made to Shioda's stances being forward based it seems that many interpret this to mean that weight is completely forward ALL the time. That is just not true. The modern day teaching is a 60/40 split with weight forward. Terada sensei writes that "the weight is not in the middle but slightly forward of middle".
Terada sensei's writings also allude to that the exercises go beyond just learning to shift weight properly but to be able to shift weight properly with the intention of coordinating the power generated from lower abdomen, feet, hip and elbows and apply it wherever needed throughout the body.