This is really, really cool. Thanks a lot for posting, Ryuku. I take it these methods are very uncommon in Thailand?
Reminds me of some of the stuff you see occasionally in boxing, e.g. tying the feet together, using a Reballdo, holding a tennis ball under the chin, etc.
Edit: How do you (and others) feel about punching with resistance bands. I have heard both good and bad things about it as a practice, though I have had some physical therapists prescribe it to me for an elbow injury that's been bugging me for some time.