I'm not sure if you are familiar with folk who live in London, but they are not know to be friendly or hospitable. I had a conversation with a girl working the secondary line on profiling last week as my bag got pulled out and she was interested in my experiences of security in Asia. Sensible and informed views from her side, but not an ounce of friendliness. Same type of indifference at Fortnum and Mason - which at £50 for a lunch - you expect better.
Perhaps i transit at off-peak times, but in the last 18 months i have not had to wait more than 5 minutes at security.
The "best" experience of security is in Brussels who have installed a system with no place to put down the plastic box apart from the belt, and once the plastic box is on the belt it cannot be stopped or removed and proceeds at extreme speed. The throughput time here is astonishing.