[CGamesPlay]

I last used this feature probably more than a decade ago, but: you provide 2 passwords when decrypting. If the first password is the main volume, the second is attempted as a hidden volume. If both match, the main volume registers the hidden volume as free space but prevents writing to it. If the hidden volume doesn't match, the main volume will clobber the hidden volume.

So the main/hidden volumes really works like a duress: you might destroy your hidden volume while using the main one under duress, but that does not apply when using the main volume while able to additionally unlock the hidden volume.

If you are in a situation to need to worry about any of this, you're probably going to jail for one reason or another, anyways.

[gruez]

>So the main/hidden volumes really works like a duress: you might destroy your hidden volume while using the main one under duress, but that does not apply when using the main volume while able to additionally unlock the hidden volume.

The problem is that if the main volume doesn't have any signs of activity, then that's highly suspicious. Why are you carrying around a laptop that's mostly empty and hasn't been used in months? Why is it that despite seemingly not being used in months, there's physical signs of wear, like scratches or dust accumulation? If you do try to make the main volume seem "used", you run the risk of accidentally overwriting your hidden volume.

[CGamesPlay]

> If you do try to make the main volume seem "used", you run the risk of accidentally overwriting your hidden volume.

No, because during the normal use of the main volume, you provided the hidden volume password, so this was never a risk. So the the obvious answer to your question is therefore: use your main volume most of the time. Only switch to the hidden volume when you're doing your hidden activity.

FWIW, I also think that the whole scheme is better applied to external storage volumes rather than bootable OS volumes: a flash card with a main volume containing things a reasonable person would want to keep from accidentally being lost (tax documents, bank statements, and so on).