I'm afraid anyone waiting for OSS to take effect at any UK airport - not just LHR - will have to be extremely patient!

The current secondary screening at LHR is not the choice of the airport - if they could get away with employing less people and charging the same transit fees they would - but that of the UK Government which regards its security processes as more stringent than anywhere else in the world, and therefore there is absolutely no trust of incoming passengers who have originated in a country other than the UK. This includes our partners in the Common Travel Area, The Republic of Ireland. Anyone transferring from a non-UK airport will have to pass through security, a situation that is unlikely to ever change.