[rhn_mk1]

Will it though? What if you had some bad sectors which became unwriteable and now contain sensitive data forever?

[Gordonjcp]

They won't be readable either, if they're that bad.

[rhn_mk1]

Even if not all bits can be error corrected successfully, surely there's enough correct bits remaining to recover some secrets.

A 512-byte sector with 100 bytes stuck is "unreadable", but I wouldn't want my secrets to be read out in some raw mode from the 412 good bytes.