When a theory seems interesting, you can't just give up on it saying "Oh, there's no way to test it!". Who knows? Down the line when it's fully fleshed out, it might make predictions that can be tested. It might have a much more elegant explanation of existing patchwork theories. Ultimately you have to ask yourself whywe do physics. We don't do it to stick to some ideal standard. We do it for fun, for ourselves. To satisfy our craving for understanding.
Curiosity is a much bigger motivation that will not be arrested simply because someone points out that a theory can't be tested at this time. Every development, every idea, every thought is useful in some way or the other. If not directly, then indirectly. Ideas that are developed now can be used decades later in a new theory. We have to lay the seeds, bring out all the wayward theories and develop all the conceivable mathematical tools.
No, I don't consider any of this wasted effort at all.