I said that I could construct such an argument. I think you'll agree that I am capable of constructing an argument that uses lies. It does not follow that I think all intelligent design proponents are liars, just that I could not reproduce their arguments without saying things that are (with my own level of knowledge) lies.

(If you really want an irrelevant example of intelligent design proponents lying, http://en.wikipedia.org/wiki/Wedge_strategy )