We started learning this technique and I humbly submit this short clip of me performing ganseki otoshi. Any constructive criticism or thoughts are welcome.
I believe this is the correct way for the uke to land, on his feet. from what I understand any other way would be dangerous to uke.
When we simply do a technique from the book, as it were, the results are fairly predictable for both nage and uke ( while the skill level rises to it's next pace). But the throws in a dynamic and free execution will have a spiral effect that is more unpredictable in terms of a 'diagramed fall'. Uke could end up in just about any position depending on the dynamic rotation. For safety, one would want to practice this with alot of 'diagram' and 'prescription'. But if you were simply thrust into a spiral of this nature you would really need to tap into your tanden activate your own resonant spirals and match the fury of the movement as it lives. Tuck your head on the way
By the way, I seperated my shoulder doing this technique about 10 years ago and very nearly broke my neck (the shoulder was the 'sacrifice'). Nage can be a great support by enhancing the final spiral (like the second video in this forum) and blending with Uke even at the 'end'. That is a compromise to upright form, but it is a lot more connected to uke.
Looks like you guys have a lot of fun and that you have healthy respect for one another. I bet you'll get it to your satisfaction.