I just had to reply to John Griffiths’ letter (Herald, Nov. 22). His letter advances misunderstandings and confusion of traffic signals and makes it clear why the public should not have more say about how roads work. A flashing yellow arrow does not mean that it is about to change. It means pay attention and yield. And, indeed, it means the same thing throughout the United States – which is nice for drivers who visit from other states, and it’s good for us when we travel to the Northwest, where there are thousands of signals with flashing yellow arrows. Solid yellow does mean the light is about to change. Therein lies the difference. Colorado Department of Transportation and the greater traffic engineering community need to do a better job of getting the word out about the differences. And, of course, red means stop, and green means go. These signals allow traffic professionals to make driving safer and more efficient. Let CDOT engineers do their work. We are all the safer for it.