Last week Koyshi Dave Joslin tested and awarded my 3rd green stripe on my orange belt.
The day before he pointed out that the quick down blocks on the arms of the Y need to knock a kick so that they go behind you. Strike with the two knuckles.
After class I asked him about Seiuchin Kata, does he have the kanji? First thought was to look in the book I am reading but it does not have any kanji :(. He will look for it. Yes, it does mean "empty mind", that is the concept/principle/strategy taught with Seiuchin Kata. Munen Muso.