> It generally is, because in the vast majority of cases users will not keep a local copy and will lose their data.

What's the equivalent of thinking users are this stupid?

I seem to recall that the banks repeatedly tell me not to share my PIN number with anyone, including (and especially) bank staff.

I'm told not to share images of my house keys on the internet, let alone handing them to the government or whathaveyou.

Yet for some unknown reason everyone should send their disk encryption keys to one of the largest companies in the world (largely outside of legal jurisdiction), because they themselves can't be trusted.

Bear in mind that with a(ny) TPM chip, you don't need to remember anything.

Come off it mate. You're having a laugh aren't you?