Encrypted or not, the text editor method that you've suggested should work if the user previously used any address from his wallet.
Even if the file looks like jumbled text (due to the text editor's encoding of the binary data), there are still human-readable parts mixed in there.
The trick is to find "name" strings using a simple "CTRL+F" find command.
If there's a match, an address should follow it.

But I do not recommend relying on it when it comes with getting the balance since it can be an outdated state of the wallet and addresses that you see may only be a portion of the actual amount.