Surely, if the train is not moving (as in not working the service), what does it matter? The driver is not endangering the lives of other rail users. If they were using one whilst "tootling" along on a service - different matter! Obvious distraction there.
But using a mobile phone in a car that isn't even running can land you in hot water... why should a train be any different?
I can understand why drivers and crew members need mobile phones but I frown upon them being used in the public eye. Why? Because it's unprofessional. But then previous roles I have worked in have made my work ethic a very high standard.
What would you think if you saw someone at Asda texting or chatting on a mobile phone while waiting for a punter? I'd not think it was professional or giving Asda a good image.
For me, mobiles comes under the same rule as smoking... that I don't like people in uniforms doing it as it doesn't give a good image to the company. Then again I am warming (or relaxing) to the idea about phones.
Then again, it is what is to be expected as to the culture of the railways, certainly at operational levels. People urinating on the tracks / cess, not exactly the best view of a person and does give a view of down-trodden, council, 3rd class sort of feelings. But then this is far from talking on a mobile phone.