Hi Tom,
I find myself with much the same question. (You have already found my query wondering how to best secure a SON28 dynohub under the Lighting section).
My big problem is I tour solo, so there is not another person to watch the bikes while the other goes into a grocery to restock and resupply. In nearly all cases, I stealth camp, and the bike is laid on its side for minimal visibility behind the tent, which is low and green/grey/black and also behind at least a screen of brush. Of course, I also tour largely in wilderness areas where theft is a minimal risk, but I don't like being surprised at night. I take a Kryptonite Evolution U-lock to secure the frame/rear wheel and a small cable to secure the front wheel at present, and lock it whenever I am in or near civilization. I am not happy with this solution. The problem is, the loaded bike means the panniers place considerable standoff between the frame and most secure posts or bike racks at the rear. I am thinking of going with a frame-mounted wheel ring-lock for the rear, and securing the front wheel/fork/frame to a secure post using the U-lock. The small cable would then be used to secure the saddle rails to the ring-lock. The trouble is, all this security hardware weighs a lot, and that adds considerably to the load. Everything else I carry does at least double-duty; the locks only serve that one purpose. I did add Ortlieb security cables to my front panniers, which always seemed more vulnerable to a quick snatch, sitting out there alone on the Thorn Low-Loader front racks. The release handles for the rear bags are buried under the rack-top load, so would take a little longer for a thief to snatch and grab. On the rare occasions I do book a motel here in the States, I lock the bike in my room when I leave on foot to buy groceries and resupply.
I do always place a wedge (Blackburn Stop-Block from the early 1980s) in the front brake lever to hold the bike steady whenever it is stopped. That helps. Also flipping the shift levers to achieve a cross-chain effect for a thief starting out on the bike helps. Another bike of mine is equipped with cantilever brakes. On it, I have two front brake quick releases -- one on the straddle cable (Dia-Compe product, again from the early-1980s) and another on the headset-mounted cable hanger/adjustable stop. They are adjusted in such a way that when I stop, I just flip a lever and the brake blocks firmly clamp the front rim. Everything looks normal except the bike won't move. This, with a lock, has made me feel a bit more secure on day rides when leaving the bike to enter a store. Sadly, this solution won't work with V-brakes.
America presents a different case than Europe. When cycling through all of The Netherlands, Belgium, a corner of western Germany and part of Bretagne in 2008, I was with a partner for much of the time and I pulled guard duty while he shopped for groceries and supplies. It gave me a lot of time to observe other cyclists' locking habits. I concluded Continental solutions wouldn't necessarily work here in the States largely because we have a great prevalence of pickup trucks. It is simply too easy for a thief to stop and quickly hoist a bicycle locked only to itself into a pickup truck and be gone. This is especially true in rural areas, where pickup trucks are the exclusive franchise of drunk, mischievous high-school kids on Saturday nights.
In the end, I may well go for a Pitlock to secure my Sherpa's rear wheel, and use the U-lock to secure the front wheel and frame to a post as the lightest, most wieldy solution. The threadless headset is a new thing for me, and has greater vulnerability for theft than the older threaded/quill stem variety -- a 5mm allen key and three bolts are all a thief needs to remove the front wheel in the fork, then take things apart elsewhere at his leisure. The main thing, I think, is to *always* lock the bike, and I do. It is a good habit to develop and one I've never regretted. Simply leaving the bike unlocked in any situation invites problemsa nd provides no theft deterrence at all. It seems to me something -- anything -- is always better than nothing.
Looking forward to others' solutions and approaches; great topic!
Best,
Dan.
Eugene, OR -- USA