Re: When is koshinage not koshinage?
Koshi-nage in it's "classical" form is different from ogoshi. Ogoshi, (and almost all judo throws) have nage parallel to uke. Aikido koshinage has the hips (koshi) perpendicular to uke. Although colloquially, the lower back can also be called "koshi," the meaning is quite clear in martial arts - it is the juncture of the pelvis and sacrum. Otherwise, uke's weight will not go through the skeleton/legs to the floor
The criteria of proper throws are as follows:
- if you stop the technique in the middle, the person's weight will go vertically down through the legs to the ground. If you are higher on the back, the weight will go in the back.
- in both judo and aikido, you actually TRIP the person with your hips. You don't load them up. The effect of a proper ogoshi or koshi-nage should be the same as if you were walking in pitch dark and walked into a horizontally placed staff right in the middle of your thighs. If you load them up - or straighten up your legs half-way thru the throw to bring them "up and over," you have, in fact, restored their balance and if they are not merely a compliant uke, they'll step out or be able to resist the technique. To make it very simple, if your butt/hip joint (depending on which type of throw) is not at mid-thigh of the uke, you cannot throw them in a koshi technique. If they are not tipped forward on the balls of their feet/toes at the MOMENT of contact with your "koshi," you cannot really throw them.
- Aikido koshinage is much more difficult to really apply than ogoshi because the kuzushi/kake is much more difficult. In judo, by clasping the waist, or in other throws, using the keikko gi, you can fairly easily bind them close to you. Aikido, working at arms length, requires much more subtle timing.
Many aikido teachers have "smuggled" in a judo type throw - but if you look at the old pictures of Ueshiba M. or of the senior teachers, the koshinage they do is perpendicular rather than parallel, as far as alignment goes.
As far as ganseki-otoshi, that's really a kind of shoulder throw, like kata-guruma in judo. The problem here is, to really do this technique against an opponent who is trying not to be thrown, your shoulders have to be at mid-thigh height. The world's best at these kind of throws are the Russian sambo players. A lot of ganseki-otoshi I've seen is more a "circus" throw - uke only falls because he/she relaxes at the proper cue, and nage, body far too high and entering at an angle rather than from "underneath," throws a compliant person.