Bike thieves, Gumtree, and retrieving one's possessions

Pity your friend didn't take these down, (irrefutable proof of ownership) and pity they didn't chase down the (their) potentially stolen bike.

He did take down the details, along with photos, etc., and had his name written all over the bike, both visibly and in UV. He's going to report the Gumtree post to the police (who will of course do fuck all) and see if they're interested in following it up (hah!).

But yes, I'm rather annoyed he decided not to chase it down with a gang of heavies brandishing D-locks. When the next one gets stolen, in about six months, I shall be a lot more insistent. Who's in?