"He has a disability so give it some thought."

Someone in Upover sent me a video clip once. It was filmed by a guide dog. 
No, I am not being funny. His owner had attached a small camera to the dog's collar and has apparently been making video clips to show people how dog and human work together. It also captures other things.
One of the things it caught was someone trying to pass them on an escalator going into the London underground rail system. 
Now, those escalators scared me a little when I lived in London. I used them of course - but I hung on for dear life and hoped that I wouldn't fall off at either end because people would try to push past me.  A blind man and a guide dog using them will be in much the same position. However well trained the dog you still need to hang on with one hand - and the dog needs to be in a certain position.
People cannot pass. 
Those dogs are highly skilled but they cannot predict the behaviour of idiots.
Yesterday I was at our medical clinic. There was a man there with a guide dog. He was going in - or was about to. There was a man there holding the door open. No, not to let the man with the guide dog in. He was holding it open because he was about to walk out but was finishing his conversation with someone else. The door slammed shut in front of the dog and his owner. It was only a "look out" from me that stopped them hitting the door.
    "Thank you. What happened?"
I explained and offered to open the door. The offer was accepted and they went in. I followed. 
"Look out" you ask?  In the circumstances it was appropriate. We both had to wait and, as you sometimes do in those circumstances, we had a short chat. I told him about the video clip I had seen and how I detest people going ahead of me on an escalator and not leaving me sufficient space to get off safely. 
We talked about the current heatwave and how he had come in a taxi because it was too hot for his dog's feet on the footpath.
As I was leaving again he had reached the reception desk and one of the girls there was saying,
    "I'm due my lunch break shortly. I'll take you both home. It will give you time to go to the chemist." 
I waited a moment and then as they turned to come to the door I said,
     "And I am about to leave. Would you like me to hold the door for you?"
     "Yes please."
And out we went.
It is particularly hard for a guide dog to use an escalator and they don't like doors being shut in front of them either
It was a nice dog too and I am sorry I had to do the right thing and ignore it.