I am no longer a frequent traveller. I came back from Turkey through lhr T3 on Sunday morning, and there was no queue, and there was a surplus of both customs and passport folk.
I guess it is times like Sunday - with zero waiting, that make the averages look good.
The passport lady was pretty, funny, and happy to chat. . That is a first.
(SWMBOs passport is different to mine, and I asked why)