Thanks for the input.

BTW, how big is the kind of bottle jacks used to pry open U locks?

A couple more lonely U locks seen today:


I'm beginning to wonder if some bike thiefs play it like magicians, and relock U locks they broke so that bike owners can't tell how they did it. Incidently, I didn't find the U lock lying around the bike I was stolen last Xmas. That Abus U lock was mid-range and probably wide enough to insert a jack bottle or something.