If I create a TrueCrypt volume and secure it with a password and a keyfile, is there any way that someone who has access to my computer would be able to tell that the volume requires a keyfile to decrypt?
If not, then if I store the keyfile on my computer, along with thousands of other files, won't it be practically impossible to decrypt the volume using brute force, since even if they correctly guessed my password, they wouldn't know they had guessed it correctly, since they wouldn't have used it in combination with the keyfile, because they don't even know a keyfile exists for the volume?
According to the TrueCrypt manual, a keyfile can be any file, so they wouldn't even be able to search for keyfile signatures on my computer.
Not to mention using more than one keyfile per volume. Wouldn't this increase the security hugely, since out of the thousands of possible files on my computer, they would have to guess the exact combination of keyfiles, and they obviously wouldn't know how many keyfiles I'd used for the volume.
Please can someone clarify this for me? I'm sure I've got it wrong.