Here in Baltimore County, MD the brainiacs have a different sort of traffic calming idea....
They build an island in the middle of the road or they narrow the road down, both which are dangerous for cylist. On one road I ride they have both. The road is one lane each way with parking on both sides - each lane being standard width -12' plus I will guess another 10' of width to park the cars.
The problem with the 'traffic calming island' is that it forces the cars to move right in order to keep from hitting it - right into my riding area. If a car is overtaking me just before the Island, they will swerve over into my path or crowd me over. I always use a hand signal and move out into the lane to keep cars from trying to pass me there. The second one they neck down the road on both sides, taking up the parking lane with the curb so that I have to signal again and move left into the lane, out of the parking lane (assuming there are no cars as I always ride out of the 'door zone' which on this road is right on the while line).
So, I say they suck.