Not a fan of Sheldon's lock technique, at all.
There is at least one U-Tube video showing someone going through a mtb tire and rim in like thirty seconds with a standard muscle powered hacksaw.
When he developed his theory, the compact hacksaw was the preferred tool of the bike thief (cheap and easily 'tossed', if 5-0h starts sniffing too close).
In today's economy of cheap imports, Bolt Cutters, have replaced the hacksaw as the "go to" weapon of choice in the thief's arsenal. A small set of cutters can easily be concealed along a forearm under the sleeve of the ubiquitous 'Hoody', larger cutters can be carried inside 'lowrider' baggie jeans, snipping thru rim and tire in under 20 seconds, in near complete silence (especially when compared to any power tools).
As far as destroying the rear wheel, again, I feel that Sheldon's advice is showing it's age.
My experience in Downtown L.A. over the years has shown me that thieves have No Problem using the before mentioned cutters to snip even 'Armored' Cable Locks, freeing the rear wheel of some other victim's bike.
I very much Prefer a modified Sheldon lock up, where by I 'capture' at least one of the seat or chainstays inside the u-lock,along with the rear wheel and anchor object. The prospect of cutting through chainstay or seatstay destroying the frame as well as the rear wheel absolutely stops all but the most hardcore thief.