The art of 'zip merging' - using the outside lane when others are stationary in traffic - is the best way to clear motorway jams, a motoring expert has said.
Despite being a source of frustration for many drivers that find themselves undertaken by cars while stuck in traffic, it could prevent tailbacks from growing longer and blocking off more junctions, according to Peter Rodger, chief examiner at the Institute of Advanced Motorists.
Zip merging is most commonly used on dual carriageways that merge to a single lane of traffic, generally before a roundabout. Although many motorists frown upon drivers that drive ahead as far as possible in the overtaking lane, Mr Rodgers claims that doing so means the tailback is kept to a minimum.
"Driver etiquette means that 'zip merging' can be frowned upon by drivers in long queues of traffic, but if all available lanes are used, right up to the bottleneck, it is perfectly acceptable for vehicles from each lane to take it in turns to merge into the single lane," he said.
"This reduces the length of road the queue stretches along and prevents blocked junctions. If you are approaching a long queue of traffic in only one lane, you should stay in the lane you're in, even if it's empty, as long as you reduce your speed. Even if you have to merge further down, it is worth using all the space available to avoid unnecessarily long tailbacks."
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