Yep yep! There isn't a single prophecy in the entire Bible that bears the unmistakable stamp of being "divine".
If the prophecy is specific then one (or both) of two things is always the case:
1) There is no evidence it was written before the events it purports to predict.
2) There is no outside corroboration of the fulfillment.
If the prophecy is vague and unspecific then:
1) Who gives a flying sh!t. The prophecy can mean whatever anyone wants it to mean. (See: Nostradamus and every book ever written on prophecy as published by the JWs, and count how many interpretations they have for any given passage.)
Prophecy: FAIL.
EDIT: Oh, and lets not forget the other scenerio, where the prophey is specific AND we have pleanty of outside evidence that it was not fulfilled. (See: Ezekiel's prophecies regarding Tyre and Egypt.)