In article , Clive D. W. Feather
writes
There isn't a contradiction here. You can arrive at a box junction whose
exit [ahead] is clear, but there's a car already in the box, travelling
forwards. As long as you can predict that the car ahead doesn't stop in
the box (that would be an offence committed by him, but it would also
cause you to commit an offence) then the SI is satisfied.

What if he stops with his rear bumper just clear of the box?

If he does that with clear space ahead of him, it fits the intended
scenario above. But yes, I suppose there is another case where he
vexatiously stops just past the box with clear road in front of him.

If he stops there because there's stationary traffic in front of him,
you are at fault because in the SI prohibits entering if your:

"vehicle has to stop within the box junction due to the
presence of stationary vehicles.

But doesn't actually say *where* those stationary vehicles are. In this
case they are one ahead of the car in front of you.

[This has happened many times at the Castle Hill traffic lights. There's about a
car-length between the stop line on Victoria Road and the box, and another two
between the box and the next stop line.]

That's a generally very difficult junction.
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