quote: My issue is that surely the same reductionist arguments that apply to ID - i.e that the phenomenon can be better explained by chance and the laws of nature - must also apply to human activity.
Assuming you are just discussing the dichotomy of intelligent activity against unguided nature this is far from obviously true. We cannot, for instance, ignore direct evidence of human manufacture, nor can we assume evolution given objects clearly incapable of evolving.
I suspect that what you mean is that since ID writings ignore arguments which apply only to human created objects there can be no such arguments. Phrasing it like this, makes the error far more obvious.