jw,
That is an interesting question.
I always remembered the account in Matthew 12, where the pharisees attributed Jesus' ability to cast out demons to satan. Jesus then went on to tell them that blasphemy against the son of man would be forgive, but blasphemy against the holy spirit would not.
I have always struggled with that verse, since it seems counter to Jehovah's nature that there is a sin that would not be forgiven. Nevertheless I have always been VERY careful not to attribute the works of other to satan.
With that said, I think the whole game of crediting success to Jehovah is a dicey game. Naturally we want to attribute any success we have to Jehovah, it gives us instant spiritual "street cred". On the other hand, if we do it to much we risk making Jehovah look bad when we make fools out of ourselves. Naturally, Jehovah does not deserve credit for the mormons falsely claiming that native Americans are related to Jews in the face of irrefutable DNA evidence.
And what about anyone who is successful? Does Microsoft have Jehovah's blessing? What about people who simply are using good practical methods and processes that naturally lead to success? Is it possible for instance that the Jehovah's Witnesses might have his blessing, but at the same time they are using very effective methods to grow membership and maintain loyalty?
What might those methods be? Would JW for instance be as effective if they recommended that all read any argument or look at any fact that might support the explanation the JW are not his organization? I mean if they have Jehovah's spirit, it shouldn't matter should it?
Shouldn't the truth always welcome questioning and doubts because it knows it's quality will be proven and our faith made stronger in the light of honest examination?