Good advice, even on 25 mph side streets. But in the morning rush get used to being honked at from behind, especially by those involved in law enforcement who don't worry about tickets. What's really annoying is when a cop tries to get you speeding by coming up too fast on your rear. The cruise control does not play along and says "hit me!".
Here we have the exact opposite problem. We have state troopers that like to drive about 5 under and clog up traffic because everyone is afraid to pass them on the 4 lane (288 N into Houston). Then, occasionally, you get the guy who thinks it's some grandma slowing down traffic and he tailgates and roars past everyone - only to slam on his breaks when he sees the real reason. Always good for a laugh.