The xkcd method is a truly random string with 44 bits in the example (4 words each chosen from a 2k dictionary). There is no better way to crack it than brute f

The xkcd method is a truly random string with 44 bits in the example (4 words each chosen from a 2k dictionary). There is no better way to crack it than brute force. The words are just a rendering of a 44 bit random number. You could also render it as 44 digit binary number or an 11 digit decimal number or as an 8 digit base 64 string. It doesn't matter; it's still a 44 bit number and requires exactly as much work to crack.