It's amazing how naive some can be to data protection. If the data was in hard copy form and, for example a matter of national security, we would have to be the equivalent of James Bond to break into a secure building.
It doesn't surprise me, because in my old Amiga days it was recommended (can't remember by whom) to turn it off for at least 30 seconds before switching it on again. In reality I don't think it made much difference, but that machine had 1Mb memory as opposed to the huge amounts on machines these days.
'For example, where information stays in a computer for around 15 seconds under normal conditions, a laptop cooled to about -50C will keep information in its memory for 10 minutes or more.'
Does that really pose a significant security threat?
I can see that I'll have to stop storing my notebook in the freezer, then. What a pity.
I'm all in favour of good security precautions, but there is such a thing as taking it too far, so in the absence of a reply from Gandalf, I'll give this one a big fat "Meh!" and leave it to MI5 et al to worry about this.