how to turn off spamassassin entirely on a per-user basis

I have searched and searched and cannot find a configuration directive that you can put in .spamassassin/user_prefs that simply turns off spamassassin entirely for that user - meaning that SA will immediately return with exit code 0. In the FAQ it says to whitelist the user, but I would prefer not to have to incur the CPU cost of processing all those regexps if the user does not want it.

What is the right way to do this?

I guess I am not the only one wishing to do this as these folks seem to have developed their own solution:

http://www.ccs.neu.edu/howto/howto-spamassassin.html#using

We have SpamAssassin.pm version $VERSION = "3.001008" spamass-milter 0.3.1_3
sendmail 8.14.1

on a FreeBSD 6.2 system

• Alex Aminoff BaseSpace.net National Bureau of Economic Research (nber.org)