I think out of courtesy, anyone who goes for an interview whether it's with a TOC or not, should be told the outcome in a few days. But sadly this doesn't always happen.
I went for an interview in November last year for a role with a company (not in the rail industry). They didn't contact me at all!!! I accepted my present job so I wasn't too bothered about the other job. I did however contact their HR just before Christmas and advise them I had accepted employment elsewhere as they had never contacted me about the outcome of the job interview.
The girl in HR didn't even know what I was talking about when I rang!!! Needless to say I left it at that.
CJ