Truth vs Usefulness of Theories
1. Speaking about the ‘use’ or the ‘results and effects’ of theories has a very venerable ancestry in the western philosophy. It is called “pragmatism”, if the ‘truth’ is coupled to the ‘uses’ and ‘results and effects’; it becomes “instrumentalism”, if the notion of truth is dispensed with. So, it might be useful if you were to familiarize with their arguments. (There is nothing specifically ‘Indian’ with these claims, nor is there (of course) any need for there to be something.)
2. If you do not familiarize yourself with these philosophies and want to discover the wheel all over again and on your own, you get trapped in inconsistencies, which make it difficult to carry on a conversation. For instance, here is what you write: “it is less interesting whether that statement is factually and objectively true, but what results and effects that particular description of the world has on our actions.” Let me identify the inconsistency first and indicate just one other problem.
You speak of “a particular description of the world“. If it is a description, then the predicates ‘true’ and ‘false’ are the only ones we can use to judge it: some statement purports to be a description of the world, and we can judge whether it fulfills that goal or not. You cannot speak about a description of the world and, at the same time, dismiss the use of the predicates ‘true’ and ‘false’ as “uninteresting”. These predicates are the only ways of judging a description of the world.
Now to the problem. The ‘truth’ or the ‘falsity’ of a description of the world is a very good reason to choose or reject that particular description. In fact, as I have just noted above, that is the only reason that is rationally defensible. Otherwise, one could just as well suggest that one chooses the fascist theory, even though it is known to be a false description of the world, because of its ‘uses’ and ‘results and effects’ both of which are salutary to the one who chooses it.