Indeed. Caesar Ciphers seem to be the hardest it gets. Did you notice that this gang cryptanalyst actually described the famed "ROT-13" as a method the gang members used?
echo -n word | \
> wm --rot13 --words stdin | \
> wm --rot13 --words stdin | \
> wm --rot13 --words stdin
result: jbeq
echo -n word | wm --rot13 --words stdin
result: jbeq