You clearly do not understand much about dogs. Contrary to popular belief, guide dogs for the blind, do not, never have and nor will they ever decide when to cross the road. They are dogs. Trainers do not sit a dog on the side of the road, hold its head, move its head from side to side, and say, see those cars there, we have enough room to cross now. Dogs CANNOT judge the flow of traffic.
Actually I seen a dog doing THAT.
I was walking to school and there was a runaway dog a few meters in front of me. I was afraid of it at first but soon I figured that dog means no harm to anyone - it's just going the same way as I am. So I was following it for whole 25mins.
And I was totally surprised by its behavior!
It was using sidewalks, it never crossed road in other spot than the zebra(unless there was really no zebra around) and it did stay and wait for the cars to pass or stop. Each single time! Even if it had to go considerable distance to the crosswalk and passing the road on spot would be way faster it was still going to the zebra. There was quite a few roads to pass on the way, including one with heavy traffic and one with lots of parking spaces and sideroads (you not only have to pay attention to the cars on road but also consider the cars going from unexpected places). It correctly judged the situation in all cases.
I have no idea if the dog was trained or just a really smart one but it was behaving like a human. It certainly knew where it is going, where the zebras are and how to behave when passing a street in multiple different situations.
There was no crosswalk with lights on the way though so I am not sure how it would behave on one. But after seeing its behavior I believe that even if it couldn't recognize the light color it would still pass safely - waiting for cars to stop or a big enough gap between cars.
Edit: It was something like that:
See? It moved towards the street looking its left, waited for car to stop(let the car that didn't stop pass and moved to show the next car it wants to pass), started walking while looking right, realized the car on right is moving too fast, stopped, realized the car on right stopped and then safely passed the street.
10 Mar 2015, 3:27 pm
