So that's why the bags take such a long time to come through?

Ignorance is bliss, goes the saying, and indeed there are times when you find something out which perhaps you would rather not have known about.  So, a somewhat worrying story that incoming luggage at Birmingham airport is routinely being searched by Customs before being put on the carousel - that is, without the knowledge or presence of the owner.  What is perhaps most worrying is that this is it seems perfectly legal - HMRC appear to have wider and more draconian powers than even the police.  And although this came to light at Birmingham, I'm sure it's happening at other airports as well.  So if you're carrying anything you would not wish to lose, it's best kept in your hand luggage!