[nullc]

You can use a 10-bit "common english" wordlist that has no exceptionally rare words and code your 56 bit values with just 6 words.

It's not clear that the markov property helps memorability much when you're still left with lots of structurally incorrect punctuation.

[jbclements]

try it out! I found this style of password (horse-battery-staple) to be much longer and less memorable. The proof, of course, is in the pudding. The next step (for me) is to conduct a reasonable experiment to discover whether or not these passwords are memorable.