Magic you do not seem to give credit where it is due.
As I recall the miners took on Heath and he called a general election to settle the matter of who ran the country, him or the miners. The people said it wasn't him.
Therefore when the nasty Tories came back to power they had to make sure that they didn't have those lovers of fairness and solidarity, the miners, bringing the govt down again. So with big incentives to produce more and more coal, stockpiled at power stations and pits, when the strike came, as it surely would, it was defeated by the miners own greed. Sometimes the truth hurts doesn't it Magic.