I don't quite think you're 100% on what you are saying, D. Kurz puts emphasis on dynamic stretching, which
directly crosses over into any striking art. Give me any student, be it TKD, MT or Kyokushin, and with one session of dynamic stretching, they'll be kicking a lot higher than with any type of passive, static, or isometric stretching.
As a side note, Kurz holds BB in Judo, Kyokushin Karate, and TKD. I've seen him throw a roundhouse at a focus mitt held almost 7 feet high. Believe me, what he preaches he practices, and the results show.