We tried tying our arms together with old himo (laces) above the elbow and then performing kihon men. As you can see from the pictures, students were told to tie their arms together quite tightly. Tight enough so that some of the kids complained of discomfort. One was even prompted to exclaim, "Oh, my precious elbows!" which is about the second best thing I've ever heard said in the dojo.
But interestingly there was very little impact on people's ability to perform basic men cuts. Both from my observations, and also from self-reporting after the exercise. Most students reported either no difficulty with their technique or an improvement in their technique. Why?
However in the context of a Kendo club that teaches fundamentals to a wide range of ages and abilities, the desire is to find the most effective, efficient and easy-to-understand way of using the shinai, that nonetheless still matches the logic of using an actual sword (刀法 - toho). I think that this exercise is a great way forward in this respect.
If you try it out yourself, please leave a comment and let me know what you think. We only used it for kihon men. Next week we might try kote and do as well. I think it might even prove more useful there too, as the position of the elbows in the cut has an important influence on which part of the palms of the hands make contact with the tsuka, and how tenouchi is employed, which again has an impact on accuracy.
The only drawback is that it does make reiho pretty much impossible!