[CTRider]

Originally Posted by RichLockyer

I don't have any more faith in ABC than NBC.

At that size intersection, 4.5 to 5 seconds would indeed be within standards, but like I said... on a modern solid state controller (and any controller made since 1980), it is impossible to program less than 3 seconds of yellow. The controller software will not accept the entry.
The old electro-mechanical units designed in the 1930s? Sure... you can adjust the pins to do anything you'd like.

They didn't say what the system was. I only know what I saw.

The short green time is another story. A typical minimum green will be anywhere from 2 to 4 seconds. Max green will be dictated by the coordination cycle time. With a 55mph limit and 8 lanes, there is going to be a lot of time needed out of that cycle for the through movements, so the engineer has two options.... run a longer cycle time, which increases delays for people on the side street, or take the time away from the left turns and the side streets. 7-10 seconds is a very common max green for a low-volume left turn.

I've seen very short green arrows at very high volume intersections - with no chance to turn during the cycle since the "yeild" mode is disappearing from many intersections (which I feel only encourages people to run a red arrow).

One intersection near me has a 4 second green arrow where 18 wheelers headed toward a distribution facility often turn. A single truck can't even complete the turn in the time the light is green, much less allow anyone else to get through it behind them.

If only one or two cars are present, the controller will only time the minimum green. Additional cars in the queue will trigger extension time that will hold the green until the timer reaches the max green.

If the signal was timing 7 seconds on that left turn no matter how many vehicles were waiting, then it's possible that it was an electromechanical unit with no vehicle detection system.

That's the problem. I encounter many intersections (even rebuilt ones with new hardware) that, while the use a tripper to detect a car, they are purely timer based to set the time that the light stays green. Likewise, there is an intersection near me with new LED lights that will trigger green arrows whether someone is looking to turn left or not.

On the other hand, a rather busy intersection near it where turning left without an arrow is very difficult has a short green arrow and the tripper refuses to detect motorcycles. While a yield green is provided, actually using it is unlikely since oncoming traffic is pretty steady there due to the volume on a narrow section of road (the intersection is just up the road from where two lanes combine into one).