Tactical noting is tricky. It's a rotten substitute for the Alternative Voting system we rejected (or rather 28% of the electorate rejected most people didn't vote), unsatisfactory as it was as a system.

But it probably made a diifference in a lot of places where Green voters went for Labour.

I imagine there must be a lot of Scots wishing they hadn't saved the Tories by their tactical voting. Alright, they've made Nicola Sturgeon back off from a referendum, but she'd likely have done that if Labour successfully pushed for a Brexit that would involve some way of helping the Scots have some special status with the EU that protected their interests.