When I was taught one of the Matayoshi sai kata (There are three I'm told. I know only one.), I was told that there were two "throws" in the kata, both directly following a spin-around, the first a single throw aimed at the opponent's foot, the second a double throw for both feet (I am assuming that most Matayoshi practitioners will know this kata). This is very problematic. The distance that one can throw a sai without it spinning beyond a viable angle is very limited and a foot is a very small target, especially coming out of a spin. I don't think that it's practical at all, especially within the confines of the kata. Aside from the dubious distancing, in the first case you presumedly pierce a foot, then draw a spare sai from your belt and stab. It takes a long time to draw that spare, what is the opponent doing during that time? And if he was close enough to stab directly out of the spin, why not? In the second case, you pierce both feet and then turn your back on the opponent without further ado. That opponent is injured, but still has a weapon and is now really intent on hurting you and is at a distance to do so. In reality, I don't think that one could reliably throw two sai and simultaneously pierce two feet. Put some patterns (which won't defensively move) on the ground and try it. If you can get it consistently, you're way better than me. These "throws" must be something else and the geometry of the sai coupled with the structure of the kata can inform us here.
If one looks at kata as a compilation of sequences instead of individual movements, the structure becomes clearer. In this case, and not in all, the sequence segregations seem to correspond to the major directional changes. One sequence North, one West, one East, one South. One could argue that there are some unnecessary repetitions in each sequence and we could debate the reasons for such, but the kata is still primarily a four sequence set. Using this structure as a guide, each spin is the culmination of a sequence that should render the opponent unable to respond (dead), so we need to look at the preceding movement and the entire sequence for guidance. The tines of the sai can hook or capture and be used as a fulcrum against the body. My interpretations are too gruesome to print and much more realistic than throwing-away your weapon in a questionable attempt at minor injury.
If this proves reasonable to you, then you can look at the other silly interpretations (at least as explained to me), stabbing then hitting in the groin, punching with the sai (you're likely to damage your thumb joint), four blocks in succession; all these can be much more effective when seen differently and as integral parts of a sequence. The difficult part, as with all kata, is working out a viable analysis.
I continue to be baffled, not just in the martial arts, by how easily folks will accept dubious "facts" when they come from an "authority". I have always told my students to question everything that I show them (and, to their credit, they do). I might be wrong and they might find a better resolution and they need to, independently, resolve it themselves. Of all the enjoyment that I get from training, the debate is what I prize most.
