I'd avoid locking an expensive bike at that same location. Crooks tend to be both lazy and creatures of habit. If you lock an expensive bike in the same spot, the same guy is likely to try to take it.
I sometimes have to lock up in downtown Houston at night. My favorite bike for that was a 1983 Trek with Reynolds 531 frame and fork. It had been spray canned an ugly shade of green. It had dents, scratches and surface rust. The wheels looked old and generic (they were actually race-quality, circa 1983). So, it was a bike that rode like a $2,000 bike, but it looked like a $20 bike. If I locked up to a shiny new Wal-Mart bike, any crook would have taken the Wal-Mart bike first.
Check into the possibility of bring your bike inside. A friend of mine is insistent on bringing his bike inside whenever he can. So far, he has convinced the owner of his favorite coffee shop, the neighborhood cafeteria, and his employer. Recently, he talked the guards at a museum into letting him lock his bike up in the inside coat room.
But, lock at the exact spot your bike was stolen? Don't do it.