Most people around there seem to be going somewhere in a purposeful fashion, and that usually involves going along the M25.
Perhaps a bit off topic, but do you think that most people these days follow line features - or is it the case that they have their Mark 1s firmly attached to the map page of their Pilot III where they are following a track either towards a beacon, or towards some IFR waypoint they have found that happens to be near a suitable turning point.
I don't know of course, but I would bet that the amount of pure map and compass line feature following going on below the TMA has dropped off dramatically in the last few years.
This may well account for your experiences around the M25.