Here is is with one extra hand holding on:
This is almost it. But I want to learn the other version, which is hand over the head (toward the floor).
Here is the correct version, and a great view of it. The key seems to be to lean away from the pole, so that they bent arm stabalizes you. So far I have only been able to attempt this with my body up against the pole. This doesn't work at all and I slide straight down. Clearly I need to lean away from the pole to take some of the weight off the one hand that is holding on and distribute it more toward the arm that is hooked on the pole. And I need a spotter to attempt this: