Well personally, I think the surest way to make a man complete the impossible, is to tell him that he can't do it. But that said, SHOULD he do it? Like others have said, I vote an emphatic "no". Like others before you, traveling across the great state of Kansas, as a first tour, on a single speed, would be a miserable experience and not one I'd enjoy with any amount of miles under my belt. It would be a grueling, mind-numbing ride.
smudgy recently did this ride and posted a video. He is a seasoned veteran and I think given all he knows, and with all of his touring specific equipment, it was tough.