What's the recommended method for locking a joint temporarily

[vburovIS]

We've tried adjusting the dampening to really high levels, and it almost solves this, but there's still some movement.

We also tried setting the joint type to fixed, and that creates a requirement for saving and restoring the position, however this an awkward solution and at many times falls short.

What would be the suggested method for locking a single joint on a chain?