thats somewhat bullshit, because rubber hose cryptography is almost as much fantasy as what they critize. What is depicted is likely mabey %1 of all scenarios where encryption would help you.
Beating the password out of someone is more an act of romantic fiction, than standard practice, just about anywhere in the world. While XKCD recognizes that most nerds obviously aren't James Bonds, what they miss is most digital adversaries aren't James Bond Villans either.
1. Most of the time, the person is simply going to either steal, or subversively copy your encrypted disk, so you don't even know they are looking for it. Read: what the NSA or any other wiretap is doing. They count on suprise that you don't know your being monitored. Hence they can't hit you, and expect that you remain unaware they are after your data. If they can't break the cipher, they can't break it. More likely, its not going to be a three letter agency, and just a common theif, who, will not have the resources or ability to try beat you for the password, and certainly does not want to confront you, just get your information without you finding out and changing your passwords.
2. Another situation is where they do confront you, but they simply don't either have the political will to beat you for your password. More common than you'd think, because, well, simply put, beating people doesn't make a regime popular with its constituents. Your going to have to be accused of something fairly bad before it becomes acceptable. If you have a hidden encryption scheme like TC does, and they don't know if its there for sure, they could beat you all day long and they'd never know if you were telling the truth or not. Torture is not effective. This has been known for centuries. Despite what the defeatists will tell you. Torture in war is done more to break the spirit, will and emotions of the enemy than it is for information. Or just for the kicks or emotional benefit of really pissed off angry people.
you can look up US case law on this.
3. If your adversary is in the government, your adversary might not be the entire government or entire system. Encryption that police cannot recover on their own, might help you, if the cops are crooked as shit, but the DA, Judge, or someone else in the system cares. Encryption that can last long enough to make it into the court room, can save your otherwise wild and henious accusations against police misbehavior. Don't give the cops the opperuntity to tamper with the evidence, or force them to hand you a subopena or warrant, or hold out on giving up your keys until talking with a lawyer will give you many more options.