I've been watching this story from afar as we moved to Switzerland last year so aren't actually in the UK any more. However I thought it might add another perspective... I'm a British 'phone cacher' but have found caches in several countries now including in central London (including just off Whitehall), Berlin (an ammo box), Chicago, Barcelona.... The whole Wetherby story makes me laugh, cringe, and worry about my next cache in equal parts...
I wondered if GAGB have ever thought about involving politicians in this whole process? I'm a political lobbyist and (before I moved to Switzerland) cached whilst attending the political party conferences (now that's security gone crazy but still no problems with the caches) and talked about caching to a few friends who are MPs/MEPs/Lords. We could hold an event at Parliament, with the support of the All Party Parliamentary Group on Rambling perhaps, invite senior police officers from all the Forces (who would turn an invite to an event at Parliament down?) and explain about caching. We could even take them to find the cache that's only 5 mins from Parliament. It needn't cost a lot to do and we could even turn it into an event cache and make them all join geocaching.com!
Just a thought and I'm happy to help if I can...
Bunny
PS Deci I thought your interview on the BBC was great and thanks to all the reviewers for their hard work.