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Yellow Box Hesitancy

The highway code rule 174 states:

"You MUST NOT enter the box until your exit road or lane is clear". 

This means each driver should wait until the vehicle in front has cleared the box and left enough space on the exit side to fit their vehicle before proceeding. In reality very few people actually drive like this, especially when they can see the road ahead is clear. However the problem is they risk getting a ticket if the car in front comes to an unexpected halt. So what would happen if everyone drove in this 'highway code' driving style? I have carried out a video simulation to show the impact:

As you can see, this kind of hesitant driving style, which enforcement is designed to promote, significantly reduces traffic flow and therefore increases congestion. Of course the yellow box may reduce blocking in another direction but this reduced flow needs to be taken into account in the design process to see if the box has an overall positive or negative effect.

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