I believe in CA they they are not allowed to use Radar on the highway. If he use LIDAR, and not sure why he did not just pull you over right away. It sounds a bit suspicious to me. When I lived out there it was very unusually to get a speeding ticket on the highways, they usually got you for lane changing and tailgating since those caused more accidents.
Anyway, I believe you are correct if you do TBD and loose, traffic school is not an option. Buy you can appeal and TBD and go in front of a judge.
If you interested in fighting the ticket check this sit out.
http://www.radardetector.net
There is a guy on there that is very knowledge about CA laws and another guy that knows everything you need to know about fighting LIDAR tickets
Lastly, check this site out about CA laws and fighting tickets.
http://www.helpigotaticket.com/index.html