Is inerrancy expendable?

I'm struck by how it's becoming fashionable for some evangelical apologists to trivialize or jettison inerrancy. Let's take a comparison: consider the dispute between Calvinists and open theists. Now open theists have a number of straightforward prooftexts for their position. There's nothing subtle about their prooftexts. What they claim lies right on the surface of the text. Therein lies the appeal.

Calvinists reply in various ways. The open theist interpretation runs counter to other things the Bible says about God. In addition, it fails to take anthropomorphism into consideration–as well as the distinction between propositional and performative language.

The basis of the dispute is that Calvinism and open theism represent incompatible views of God. If Scripture is true, then both interpretations can't be true. So the question is how to harmonize these prima facie contradictory representations of God. 

If, however, Scripture is fallible, then Scripture may teach both open theism and Calvinism. Different Bible writers with inconsistent opinions of God. Or even the same Bible writer with inconsistent opinions of God, depending on his mood or situation in life.

So on that view, the Bible doesn't show us what God is really like. It only shows us what Bible writers thought God was like. It reduces biblical teaching to a collection of theological opinions. Indeed, divergent opinions. But that makes the Bible worse than useless. 

What good does it say that if Jesus rose from the dead, Christianity is true, so we can dispense with inerrancy? But if we dispense with inerrancy, then what is Christianity? If you ditch inerrancy, then Catholics, Calvinists, Arminians, open theists, and so on may all be justified in finding their theology taught somewhere in Scripture. There's nothing to harmonize. And there's no way of telling which, if any, of these disparate positions, is true or truer. When you repudiate inerrancy, that's a recipe for religious pluralism.