Charles Hill wrote:
Seki Shihan, at the Aikikai Honbu, insists that uke does not step off the line. He actually goes around the room and physically corrects every person. In other classes, teachers taught differently. So I had to learn how to attack one way in one class and another in another class.
I remember that very well... Seki Sensei (7th dan) doesn't normally talk much in class, but he certainly growled "masugu, masugu" (straight, straight) at me when I kept on veering to the side with yokomenuchi. He wouldn't let me go until I moved in a straight line towards him.
I guess Aristeia is right in that it all depends on nage's kamae. From my limited experience, nage's hands tend to be close to his hara, so it is easier to move in a straight line to attack. However, in situations where nage's arms are slightly higher and longer than usual, it might make more sense to slide off-centre to strike.
Just out of interest, I have also noticed differences in the initial hand position for yokomenuchi. Some people start like shomenuchi, with the hand brought to the forehead. Others start with the raised hand to the side of the head (which feels easier, but one has to be careful that the swing isn't too wide). I'm also curious as to what people think about this