How would you counter a chin-na technique like this?

If all other things were equal, chin-na is the nemesis of Wing Choon Kungfu, because it is disadvantageous for a small-sized person to be gripped. But a good Wing Choon practitioner can turn a weakness into a strength. This is what Grandmaster Wong asks the course participants to do. He shows them a formdiable chin-na technique and ask them work out the counters on their own. The participants responses are excellent.