My nitpick with older installations is the delay in indications from mechanical controllers, especially in cities like Philadelphia , where they can't afford new controllers for retro intersections. Has anyone noticed
Sticky cams and fingers are usually to blame, due to poor maintenance.
I used to see that from time to time in New York City.
Also, some controllers, such as the Crouse-hinds KS controller, typically featured a 1/2 second "dark period" when the lights changed.