[DonRotolo]

No, brute force is never efficient, but in some situations it can be useful.

Not in this case though. This is world-class encryption, with a key sufficiently long and diverse to preclude any brute force attack, or dictionary attack, or (really) any attack at all.

Frankly, you'd have a better chance of kidnapping Frank* and "torturing" it from him, or breaking into FIRST and rifling through their filing cabinets** to find a copy.

In other words: Yes, it is a convenience to have the manual, but it is as worthless as snow in Juneau*** until Kickoff.

* I bet he doesn't even know the decryption password anyway, so leave him alone please.
** I also bet they didn't leave any hard copies anywhere, anyway, so leave FIRST alone please.
*** Juneau what I mean?