But if one is indeed wishing to employ the tactic of aiki within this technique then it is important, I believe, to note that we should not match yang moves with yang moves. This is a loss of harmony and thus of connection and blending. Physiologically speaking, this is manifested in the clashing of one's arm with nage's strike, and/or the losing of one's balance at the moment maai is closed to a range of close-quarter engagement, etc.
Nice post but a couple of small points:
When my instructor performs this technique there is no clashing...indeed, whether he uses an early timing (as you suggest), or when he uses a late timing...there is no feeling of clashing. There are times when I can also achieve this to an extent (and some uke are sooo much easier than others), so I know that its not just my instructor that can do this.
I have also often been told to work the pushing feeling rather than the pulling feeling...and to eventually get to where you are really doing neither.
Aiki has many different deffinitions depending on who you talk to...in terms of this discussion I am reminded of the described use of aiki in ippondori ura from the ikkajo syllibus of Daito ryu...a pretty sophisticated use of timing, that.