Bogofilter 0.12.0 includes a new file, bogofilter-tuning.HOWTO.
It's in the bogofilter/doc directory and replaces README.Robinson.

Directory bogofilter/tuning has been added and contains scripts for
running tuning experiments as described in the new HOWTO. See file
bogofilter/tuning/README for more information.

Bogofilter's man page and help message describe the many command line
switches.  They have been divided into groups (help, classification,
registration, general, algorithm, parameter, and info) in both
places.

Bogofilter 0.12.0 has three new command line switches for rapidly
scoring large numbers of messages.  These "bulk mode" switches are
especially useful for the tuning process.  The new switches are:

-M - allows scoring all the messages in a mbox formatted file.  If
used with "-v", an X-Bogosity line is printed as each message is
scored.  Using the "-t" (terse) option is recommended to reduce the
amount of output.

-B - allows scoring of multiple message files, with each file
containing a single message.  With this option, bogofilter expects the
file names to be at the end of the command line.  If used with "-v",
the file name is included in each printed line.  Using "-t" is
recommended.

-b - allows scoring of multiple message files, with each file
containing a single message.  With this option, bogofilter reads the
file names from stdin.  This option can be used with maildirs, as in
"ls Maildir/* | bogofilter -b ..."  If used with "-v", the file name
is included in each printed line.  Using "-t" is recommended.

New script bogolex.sh converts an email to a special file format that
contains the information needed by bogofilter to score the email.
Its use speeds up the message scoring done by the tuning scripts.  The
script is described in more detail in bogofilter/tuning/README.