It is conventional, yes, but the do not overfly areas are still applicable. In reality, apart from making the circuit oddly shaped and large, it's not much of an issue as there are easy visual ground features to follow/avoid. The potentially most difficult 'gotcha' is after descending deadside over the lake then threading between the villages to join downwind.
Ironically, the Bentley Priory home for the well-heeled elderly has 2 Spitfires proudly presented on the driveway and an on-site BoB museum but are not keen on being overflown by lesser aircraft.
But you can buzz the Jewish cemetery to your heart's content...
Just like anywhere else, local knowledge is important; if you don't have it, try to glean it from a PPR call and/or perusing the website. Sadly the Elstree website is not as useful as it should be.
We all live under the same sky, but we don't all have the same horizon.