Piasan: The specific problem, is that ID claims to be science. Like I said, it's good philosophy and good theology.... but that doesn't make it a scientific theory.
Modern ID is the brainchild of YEC lawyer Philip Johnson. He saw ID as a "wedge" to ultimately get YEC into the classroom. Hence the "wedge strategy." This has much to do with ID being considered a creationist argument. The fact that the leading ID organization is much more about political action than scientific research doesn't help much either.
After all, we all know Who the Designer is, don't we?
I understand what you're saying but the point is "ID" isn't just this "movement", and limiting the definition isn't a valid argument. Even if someone did originally have a motive to get YEC into the classroom, we have to look at modern motives otherwise it's the genetic fallacy. There may be a small percentage that want YEC in the class room, but the real issue is whether the ID argument is YEC. It isn't.
This is because the studies of William Paley, are still scientifically sound descriptions of the anatomy. The correct design of the various anatomies he explains of which some I have read, show that the particularly correct, perhaps even uniquely correct contingencies are in the body. The cleverest solutions are present, and the features of design over-qualified.
For example when you say "we all know who the designer is don't we?" But agnostics are also IDists. That is the point, whatever design we find in the body is factual, the claims about Who or what put the design there, aren't the intelligent design argument. We obviously as Christians, proclaim it to be God, but that proclamation is one of faith, not science. But the ID argument itself, just argues that ID is present in life.
Who designed is a matter of faith or even debate. Some say life itself is somehow smart, some say aliens, obviously we as Christians believe our answer that God is the designer, is the best answer by far.
That's the real reason they reject the intelligent design in the anatomy, because they know that if they acknowledge it that this will give theists too much debate-power for God, and they don't want that, for that would go against what they see as a progression towards a totally scientific explanation of the universe including life, matter and everything else, without God in the picture.
Do you think they care if intelligent design is actually in life? Of course they don't. But by every qualification it not only is present, but is over-qualified. The field of biomimetics alone proves the design in life if more intelligent than ours for if it wasn't we wouldn't plagiarise those designs when we are left head-scratching, proving not only design but superior design-ability to our own.
Now if you as a TE say, "somehow done by God through evolution", yes - in a way that works in the sense it at least fits given God could have mysteriously led evolution towards those best designs but for those who say it is just, "E", more difficult for just, "E" given it has no intelligence. (a contradiction).
An honest acceptance of the fact of intelligent design in nature, is required by scientists at this stage. Unfortunately a hunt for truth isn't their prime motive.