[P]olitical communication is almost exclusively conducted by means of purported debate among people with different views, yet citizens seem increasingly unable to grasp of the perspectives of those with whom they politically disagree. . . .
As the social and political world gets smaller, it also grows more obviously complex, complicated, and confusing. . . . Thus a premium is placed on epistemological stability, consonance, clarity, and ease. This is why it's easy for our political rhetoric to look so tribal in the first place. . . . [Proponents] must portray their perspective as superior without actually engaging with any actual opposing views. . . . [T]he central aim of mimicked debate is not that of making a direct case for one's favored view, but rather that of making the opposing views look unintelligible and incompetent rather than merely mistaken.
This comes up in economics too, which is unsurprising, because (with apologies to von Clausewitz) economics is just politics by other means.
As an economics student, I'm very comfortable working with different models — marginalist, Keynesian/Hicksian, (neo-)classical, and a little DSGE — all with different assumptions, depending on what I want to talk about. I really don't care what models are "true"; I care about whether they're useful. So, in doing one sort of analysis, I'll count capital in money, set the marginal product of labor and capital equal across two sectors, and see what happens. So, on the one hand, I don't have a lot of respect for advocates who say this or that model is really true, but on the other hand, critics who condemn a model because it's not really really true irritate me as well. All I ask of a model is: does it help me understand what's going on in the world? Can I get a reasonable sense of the limits of the model, i.e. when it does and doesn't work?
YMMV. Please don't waste our time complaining that you do want to know what's really really true. That's fine. Go figure out what's true and come back to me with an answer, or at least an argument. I do care about what's true; it's just that I'm too dumb, and economics is, at least presently, too complicated, to figure out myself what's really true.
So... is the LTV true? Really true? Really really true? Maybe, maybe not. That's not why I use it. I sometimes use the LTV because it's mostly correct, not blatantly wrong, and it tells a certain story about what exploitation actually is and why and how it happens, a story I find compelling and informative. That's about it. Unlike most economists and economics students, my project is not to give policy advice to agents — banks, corporations, governments — in the republican-capitalist-imperialist world system. (Any, unlike some economists, my project is definitely not morally justifying the the republican-capitalist-imperialist world system.) Of course, I'm in an economics program in the republican-capitalist-imperialist world system, so I have to learn the tools and techniques to give policy advice. C'est la vie. It's good to know, and I can do it, but it's not at the heart of my project. Again, if your project is to advise or justify the existing world system, good for you. Go do it. If it's of tremendous importance that I share your views, however, you will be disappointed.