I have a challenging question for you: What does Intelligent Design predict? Stumped? Perhaps it’s because, despite the protestations by ID proponents, that it is a trick question. There is a gap between what proponents say and how they behave in practice.
There’s no doubt that if you ask a proponent of ID what it predicts they will rattle off a list including specified complexity, irreducible complexity, no useless DNA, the rapid appearance of complexity in the fossil record, etc. However, this seems to me to be a smokescreen because ID proponents often don’t act as though they believe ID makes those specific predictions.
If you venture over to the Discovery Institute to peek at their definition this is apparent:
The theory of intelligent design holds that certain features of the universe and of living things are best explained by an intelligent cause, not an undirected process such as natural selection
This sounds like something that is testable but the devil is in the lack of detail. If I were to tell you that the atomic theory were incorrect you surely would ask me in what specific manner. However, the major contention of ID in practice, as seen in this definition, is that some yet unspecified dimension of biology is incompatible with evolution by natural selection.* This could be said to be the reason why demonstrating a specific claim of ID to be wrong, like the alleged irreducible complexity of the bacterial flagellum, doesn’t in practice cause proponents of ID to abandon the theory as a whole. The details that a specific example of irreducible complexity is wrong doesn’t matter because, to them, there must be some example of irreducible complexity somewhere. If we can find no irreducible complexity, there must be some other trait which proves design.
They are, in essence, looking at a city which grew organically out of the needs of its people, conceding it looks organic but saying that if we look close enough, we know not where yet, we will find that some portion of the city was planned in some way. Making such an argument fails a test of inference when comparing design to competing hypotheses but for those that attempt to criticize the latest specific arguments of ID proponents ID will always be a shifting target.
*It’s also worth noting it could be seen as a straw-man to say evolution is undirected. In a very real sense it is “guided” by whatever currently available mutations exist which is what leads to the incompetent design we all know and loathe.