It is logical to deduce that if something is sufficiently complex it is because it has been designed.
No, it is not. The ID people understood that, which is why they didn't search for complexity, but rather, irreducible complexity and specified complexity. Everything with multiple parts is complex. The atmosphere is complex. The oceans are complex. A mountain is complex. And there is no evidence that any of them were designed.
Obviously, if someone considers a logical deduction fallacious, then they are not thinking correctly.
Correct. And if somebody commits a logical fallacy and doesn't recognize it, they are not thinking well. Are you claiming that what I have called fallacies are sound logical deductions? It seems so. But you've made no argument, just a claim that you committed no fallacy, and it's demonstrably incorrect. Of course, that assumes that you know what a logical fallacy is and how to identify one. All I can do is identify and name them for you. I can't make you understand why they are fallacies if you can't see why after I've explained it.
Irreducible complexity has never been shown to evolve through natural selection.
Of course irreducible complexity has never been shown to exist in naturalistically evolving life forms. It seems that you don't understand what irreducible complexity is or that it has never been identified in a biological system.
They have absolutely nothing to make even an informed opinion on in this matter.
It's the ID people who claim that irreducible complexity will point to an intelligent designer that have nothing, for which reason the biologists disregard their claims about an intelligent designer.
They cannot show true scientific understanding of something if their models are not supported by the empirical evidence.
The scientific model IS supported empirically. It's the creationists who lack empirical support.
Not even an informed opinion can be made, as this requires real data to build a rational belief on something.
The absence of irreducible complexity in biological systems is justification for not accepting claims about intelligent design predicated on in its presence.
It's a fact that they are there. Those are basic observations made in science.
What is "they" here? What are you saying is there?
The ID theory builds on those observations.
There is no ID theory, just a hypothesis and an insufficiently evidenced claim.
I already named several. You've ignored that.
I still don't know to what you refer here.