I'd taken a day off work to take the kids to London today. We'd done some caching, gone on a high speed boat trip, and even kept my daughter happy by letting her do a spot of clothes shopping. We ended up in a restaurant.
Bobcat said that he was exhausted and wanted to go back to Waterloo using the underground. Its a lot easier to walk I told him. I showed him the route by underground and then grabbed a random cache sheet from the bag to show him the way straight across the bridge. It happened to be the sheet for this cache and the virtual icon was right where we were.
I looked across the street. There was the author and the answer to the question. A complete fluke.
Now back home again. I've sent the email and received the confirming response so I'm now logging a find.