I think the logic in the explanations here is very clear.
They don't put a second line of security in place because Geneva security is crap.
They do put a second line of security in place, because there is no way of guaranteeing Geneva security isn't crap.
I think this has been appropriate for a long time, even going back to Lockerbie, which demonstrated the risks of trusting everyone else's security screening.
So what you are saying is that a flight from A to B may be less safe than a flight from B to C (or vice versa) because preflight security is not standard. How enlightening. How frightening. This is bollocks.
Ozzy