I use the Sheldon method as well (plus a cable for the front wheel), and have the same concerns as everyone else. Not to mention it can be a tremendous pain in the ass when locking up to a crowded bike rack. To make matters worse, a lot of Penn State's bike racks are too low to fit a 700c wheel through, so I often have to A) lock to the side of the rack, B) use an inferior lock strategy, or C) lock to a friend's bike.
As an aside, about an hour ago I locked up to a rack with three other bikes on it, and they were ALL locked through the front wheel (only) by a cable lock. I nearly wrote an exasperated note in triplicate to educate they sorry azzes.