ada77, no one said it's okay to take photos of people on an active roadway, either.
That's also quite dangerous. Look, do what you want. This is about trying to make people think twice before deciding that they should do a shoot on the tracks. Because if you look at the People section of this forum, it seems there are quite a few photographers who think it's fine.
And to me, that's a scary thing. When I work within the right-of-way of (not even on) the rails for my professional (non-photographic) work, I'm required to have the following or I get thrown off the job site, no questions asked:
Valid proof that I've passed the relevant safety training course within the last year;
A copy of the safety manual
Safety vest (safety orange, not yellow)
Boots covering my ankles (steel toes optional but recommended)
Also I need to have signed in with the safety officer and have that person or another person with radio contact with the trains with me at all times.
P.S. And even with all that, railway workers still get killed, with regularity. Same with roadway workers. The last rail project I was on, there had been a serious incident, a "close call" is what they called it, meaning it could have been much worse, but there were injuries.
That helps to make it real. I just think that these people are not taking the potential dangers seriously enough, that's all.