No idea how they know how long his password is.
It's easy to remember a 50 character password. For example, there are bound to be songs out there that you know all the words to. Take the first letter of each word in the song. The resulting 50 character mess will make no sense, and won't appear in a dictionary, but will be easy for you to remember because you know how to "regenerate" it. Add in some numbers and letters, say simple 1337speak or some other substitution cipher, and you're done. Near unbreakable 50 character password.
Example:
wywhbclyiteyjlaaysmmcyflafiabwiwiwsysfsbiaciawwthaidhidbh
First letters of the words in the first verse and chorus of Creep by Radiohead. 57 character password, utter gibberish, easy to "remember". Add in some numbers and special characters and it gets even more solid. Once your hands learn to type it, you'll hardly even think about it. Sorted.