I can assure you, that while it says 70-75 on the signs in Cali, the speed is generally 80-95 lest one would obstruct traffic. Generally speaking, obstruction of traffic (driving too slow compared to the speed of surrounding motorists in this context) is much more against the law than going slightly over under most circumstances.
I have family in the CHP who have confirmed that dickheaded officers absolutely can and will do that as you are an obstruction to traffic if going too much slower than surrounding traffic.
They had some nasty things to say about people like that, but it happens
You’re not going to get a ticket for going the speed limit
“22400. (a) No person shall drive upon a highway at such a slow speed as to impede or block the normal and reasonable movement of traffic unless the reduced speed is necessary for safe operation, because of a grade, or in compliance with law.”
