Most of my life I worked for the railways both in the UK and overseas, I now(thankfully) have no connection to them. However I'm happy to answer any operational questions that you might have in regards to such matters.
I would make one point that I think is very important in regards to railways in the UK and privatisation I had the misfortune to work at the tailend of British Rail in the UK and the lack of investment was staggering so when the government talk about how much the railways have improved since leaving the public sector its worth keeping in mind it was off the back of 20 years of underinvestment.
For me the key issue is(and indeed it's something not unique to the UK)is what are railways? are they a business or are they a public service, if you go back to Beeching Report he clearly saw it in dollars and cents and whole communities died. Does the government have a strategic responsibility to provide a sustainable transportation network(be it road rail air sea), or doesn't, if it does is the private sector capable of delivery?
To be honest until we answer these questions and reach some kind of consensus it really doesn't matter if the railway sits in the public or private sectors.