The TrueCrypt website has some detailed information on [how to backup (TrueCrypt non-system volumes) securely](http://www.truecrypt.org/docs/how-to-back-up-securely), summarised below:

> 
> 1. Create a new TrueCrypt volume
> 2. Mount the main volume.
> 3. Copy all files from the mounted main volume directly to the mounted backup volume.
> 
> 
> 

My question is: Why is this necessary? Why not simply copy the encrypted TrueCrypt container file to your backup service/device? According to step 5 of the [TrueCrypt tutorial](http://www.truecrypt.org/docs/tutorial), this container is a normal file that can be copied, moved, etc.

Surely copying this encrypted file to a possibly insecure backup medium is the simplest and most secure way to backup?

What advantages could there be to [the method mentioned on the TrueCrypt website](http://www.truecrypt.org/docs/how-to-back-up-securely)? It mentions at the start about files in the volume possibly becoming corrupted - is that relevant? In this case I'm not interested in hidden volumes or plausible deniability.