So put in an encrypted form, the password is in your head.

Use 2 or 3 safety deposit boxes, they are very cheap.

The faintest of ink will outlast the best of memory.

That's not remotely true. I get a receipt from a specific service provider every week that I could easily recreate from memory, but the ink fades within a month.

Not to be flippant, but your head is not terribly secure either.

Coercion is a thing, and despite what you see in the movies, you'd be surprised at how fast you offer the password.

But perhaps more certainly, you will at some point die, and it's probable you will do so lacking the capacity to pass the code on to your heirs. So if you want your wife and family to jnherit, well, you may want to rethink.

And that's before we discuss thd uselessness of crypto as currency where you have to go to your safe deposit box to spend any of it.

You misunderstood. Since your keys are stored encrypted in a safety deposit box, it doesn't matter if you're forced to tell your password to some random thug - they don't have access to your keys.

You can also put your password in your will, if you're afraid of not passing it to your family.

But again, how do you make the thug believe you?