I have no problem with any of that (except the Lockerbie example). I've never said there wasn't a case for checking BPs at the door. My point has simply been that it is not a security issue. One of the many problems with the hassle we all have to go through at airports these days is that so many people invoke "security" as a reason for doing things when in fact many of them are for other reasons entirely (many of which are perfectly valid: revenue protection, accurate manifests, etc). This becomes very irritating to those of us who have the brains to work out there there is no possible security implication in whatever it is we are being asked to do and yet we are not allowed to question the situation because we're liable to get hauled of to jail for pointing out that we are being lied to (this apparently makes us a security risk).
All I ask is that people involved think before invoking "security". By all means if people ask why they are being asked to show their BP at the door then tell them it is a last check to make sure that they are on the right flight (since the system does demonstrably fail in that regard), but please don't insult our intelligence by telling us that this is a matter of "security".
The Lockerbie example is a long time ago - these days the terrorists would just get on board and die with everyone else. Your boarding pass check wouldn't stop that. The answer to bombs in luggage is to screen the luggage. Nothing else will have any significant impact.