A good idea but a smart thief would do the same as he stole it so he too would have the same serial numbers as you. The chances of this happening are slim but could happen I suppose.

As far as the original story what a risky why of trying to steal a bike, imo. I would never have the nerve.

I do think engraving some ID somewhere is a smart idea, do I have it ,Noooooo, but will soon enough. Also I have heard about some form of ID in the seat tube.