Interesting, maybe, but "useful", probably not. If it were actually "useful", it would be testable. Something is testable when it has detectable consequences which can be examined. An idea without consequences is pretty much "useless" by definition. It's just ivory-tower blue-skying, fit for at most late-night dormroom bull sessions after a few too many beers.
"Untestable" doesn't necessarily mean false.
That cuts both ways -- it doesn't necessarily mean true either. And being untestable, it not only can't be determined whether it's true or not, it doesn't *matter* if it is or not (again, because in order to matter, it has to make some sort of difference to some aspect of the real world, but untestable notions don't -- if they did, they'd be *testable*).
You sound like someone who thinks that there is no possible knowledge outside of science, narrowly defined. This is called "scientism," and it has been responsible for a great deal of bad in our civilization. Such people tend to be barbarians in white coats. They reduce human knowledge to a very narrow little sphere. No thank you.