Password policy questions are a perennial fixture of IT Security stack exchange, and take many forms.
Take, for example, the recent XKCD comic on the subject:
Shortly after it was posted, user Billy ONeal asked directly whether the logic was sound: Is a short complex password or a long dictionary passphrase better? You will find answers that support either conclusion, as well as answers that put the trade-offs involved into context.
Of course, part of knowing how easy a password is to crack is knowing how a password cracker works. Are there state of the art techniques or theory specifically for a …