I have provided one based upon Behe’s “irreducible complexity” argument and it seems well in line with what the Discovery Institute is promoting. If you don't like it provide a substitute.
So if one can distinguish engineered human insulin producing bacteria as “intelligently designed”, does that mean that the other bacteria is not designed?
Appeals to a supernatural agency is not and never will be Scientific. Not unless that agency is predictable and measurable; and then it is hardly supernatural anymore is it?
So was Citrate plus e.coli intelligently designed?
Was nylon eating bacteria intelligently designed?
What exactly is your I.D. hypothesis. Hard to address it if you will not state it.
(Rolls eyes) You're determined to add complexity, aren't you?
The hypothesis would be: "this phenomenon was the result of an intentional action by an intelligent agent."
Simple as that.
Now, verifying the hypothesis may very well be difficult to do -- but the hypothesis itself is much easier than you apparently wish it to be.
For example, when confronted with our insulin-producing bacterium, we can state the following ID hypothesis: "this insulin-producing bacteria does what it does as a result of deliberate genetic modification."
One source of evidence to support the hypothesis would be to sequence the bacterial genome. It will reveal the "extra" human insulin gene among what otherwise appears to be "regular" bacterial DNA -- about what one would expect from the recombination process.
As a "scientist" who rejects the possibility of a valid ID hypothesis, you'd be stuck trying to show how that human insulin gene got into the bacterium by natural means. You could probably even come up with a mechanism -- albeit one that requires a whole lot more, and more tenuous, assumptions than the ID hypothesis does in that case.