Planes, trains and higher tax gains

On the way to work this morning I heard an interesting plan on the radio: Because too many people are flying on short, in-country flights such as London to Manchester, they want to up the tax on these flights by some excessive amount so that people will take the train instead.

I've got a better idea - one that doesn't tax us even more - how about reducing the price of the train fare instead?

Is that so difficult? The fares are stupidly expensive anyway, and the service is rubbish. This is why people fly instead. It takes the same amount of time, is cheaper and more reliable. How about addressing the root cause of the problem instead of just increasing taxes yet again?

But decreasing fares or improving reliability wouldn't increase revenues, would it?