I hate the phrase "tactical voting". A Tory supporter voting Tory in a safe Tory seat is a 'tactic' too, just a very easy one.
The problem is that we have a tactical *voting system*.
I'm in an SNP/Lab marginal. I prefer SGP but I'll vote SNP because they're better than Labour & my guy isn't transphobic. Sure I'd prefer Green, but the most a Green vote will do here is increase the accuracy of the sample—and if that was my priority, I'd write in "Automated luxury queer communism".