David Carradine had no formal martial arts training of any sort. He had received some training as a dancer when he was younger. This was a particularly aggravating fact for Bruce Lee after he was turned down for the part of Caine.
In the title sequence, the close-up shots of Caine's arms moving into position over the cauldron show his right arm covering both the dragon AND the tiger.
For the DVD release of some seasons the aspect ratio was changed from 1.33:1 (4:3) to 1.78:1 (16:9).