When pundits can pick up and drop arguments at the drop of the hat without worrying about long-term consistency, it may make it easier to appear to be winning at any moment, but at the cost of actually fighting for policies they believe in. I don't know; perhaps most of this stuff is only surface-deep and doesn't really have any effect beyond really efficiently conveying to people disposed to agree with conservatives what it is that they're suppose to agree with right now. But the idea that it's a major net plus for conservatives, I think, is unproven and highly unlikely.I think there are other prices to these stances, which are partially attributable to what has been termed "epistemic closure." Just a few years ago, Republicans would happily criticize teachers' unions but were always very quick to profess their love for the teachers themselves. No more. Now, conservative pundits are regularly going on Fox to demonize teachers and talking about how lavish a $50,000 salary (plus benefits!) is for someone who doesn't work summers. Yes, many of these same pundits also pointed out quite recently how tragically low a $250,000 salary was for Wall Street CEOs (and they didn't mention the benefits then), but hypocrisy isn't really the point here.
The point is that when conservative pundits go on conservative news outlets and bash teachers, conservative viewers get the impression that it's okay to make these arguments publicly. And politically, that's a really dumb idea. Teachers are incredibly popular. What's more, there are a lot of them, and they don't all live in liberal neighborhoods and they aren't all Democrats. Conservatives are alienating a large and very sympathetic constituency when they make these sorts of arguments, and if all they watch is Fox, they probably don't even know it.