No need to waste your time. The human brain is less than '1/10 random' as an PRNG.
Do you have a source for this ? I would like to read more about it
How about this thesis http://www.jbonneau.com/doc/jcb82-thesis.pdf with title "Guessing human-chosen secrets" by Joseph Bonneau.
I haven't read the thesis thoroughly, but there are few interesting things such as human choice of PIN in page 60.
