On 2006-10-23, Earl Purple wrote:

Most gridlock (or starvation to be more technical) occurs where there
are two signals in close succession, such that the space between the
signals is filled quickly by one side and then the other side will have
nowhere to go. Actually this is commonly the situation at Henlys Corner
for the A406 Westbound. In the last couple of weeks they have been
resurfacing and there is currently no box junction and the approach has
become a lot emptier as a result.

Going on to the Edinburgh Bypass (A720) somewhere near Hermiston Gate
was the closest to that I've seen. A roundabout with traffic lights,
and a heavy stream of traffic at 6 o'clock (me) and 3 o'clock.

Every cycle, the traffic from 6 o'clock would stream onto the roundabout
until a red appeared on the roundabout, then stop, queued all the way
round the roundabout across my entrance. To move at all necessitated
pushing out on the red as soon as a gap appeared (and before the traffic
to the right started moving).

--
David Taylor