MIG wrote:

If their
drivers followed the highway code (which of course they don't) they
would only ever start moving through a junction or crossing if there
was a full bendy bus length of space available beyond. A regular bus
or three cars might have been able to move on, but a bendy bus
shouldn't.


The problem there is that if there are two lanes, as soon as there is a
car-length space on the opposite side of the junction, the car stopped
alongside the bus will cut diagonally across the box junction into the
space, and this will happen repeatedly, so a space big enough for a bus will
never appear. This isn't necessarily maliciousness on the car driver's part,
since overtaking stationary buses is such a normal instinctive part of
driving.

The solution is to make it illegal to change lane in a box junction. But box
junction observance is generally abysmal anyway, buses being the worst
offenders but not the only ones.