They can get a pass on not being Precise. They have repeatedly predicted end dates and failed, so they can claim that they are off the mark, in terms of Precision, of the future event they claim Accuracy on, end of the world. It could be tomorrow, in terms of lack of precision, and they'd be 'right' or 'accurate'. It could be another century, in terms of lack of precision, and they'd be 'right' or 'accurate'.
The claim of accuracy in (THE REAL WORLD) ordinary science carries with it an implicit invitation to all competitors, detractors, dissidents to go take their own data and use common standards and arrive at some conclusion that validates or modifies the previous finding. If the JW leadership implicitly invited its membership to do as the Boereans did, then the claim of accuracy would be about as relevant in a religious context as it could possibly be.
But they do not! They truncate that implicit invitation by issuing the superating claim of having divine knowledge that is necessarily untestable and unaccountable. It is a bait and switch, text book fraud, scam by the numbers, like every other of their many forms of bait and switch. They speak with a forked tongue, "Test out our hypothesis!", but then bite down with the fangs that only they have the fact because they are personally and individually informed by the Creator of the entire Hubble volume. One cannot contest a fact derived from a context greater than the context within which you may observe and hypothesize. And so, the member walks away with the thoroughly confused impression that this fact is accurate, and that you the member must accept this fact that is from an untestable source AS IF you had tested it yourself.
Why be so hard on them, indeed.