Likewise, the fewer intersections (merge points) the less delay that induces. This has lead highway planners to minimize intersections, to reduce stop and go traffic. However, the unexpected consequence has been to concentrate traffic at a small number of intersections. However, this has had unexpected consequences. With very large intersections, 'free' left and rights are no longer possible, and so each turn movement has to have a phase. The more phases per cycle, the longer the cycle, and the longer the amount of delay at the intersection. Arguable, better procession along a corridor might be achieved by unifying signal timing for a larger number of small intersections along a corridor.
Traffic lights are typically time for efficient operation at the peak hour, regardless of how inefficient that makes them the rest of the time--where is why you wait for like half an hour at the cross section of a major road at midnight.
The greatest danger for pedestrians are high speeds (more serious injuries, less reaction time for the driver) and exposure time. Exposure time is a function of distance to be crossed: wider intersections are bad.
The speed at which drivers travel is largely a result of the functional geometry of the road: Wide lanes and straight aways induce speeding; narrow lanes and curves slow drivers down.
The optimal road network for drivers and pedestrians (arguable) consists of a network of narrow 1-way roads, with regularly spaced 2-phase intersections (permitted by 1-way roads), where the signals are synchronized. For automobiles, peak speeds are low, but average speeds are good, and intersection delay is minimal. For pedestrians, exposure is more frequent, but for sharply reduced times, and crash severity and frequency are minimized.
Ie, Portland, Manhattan, or the Avenues in Salt Lake City. "The standard block in Manhattan is about 264 by 900 feet (80 m × 274 m); ...the standard square blocks of Portland, Houston, and Sacramento are 264 by 264 feet" (Wikipedia, 'City Block', 10 Dec 2017), and blocks in the Avenues are 330' x 330'.
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