as invented mentioned, a closure of some but not all lanes of traffic should result in the traffic reports showing up, then Waze choosing an alternate route.
There's no perfect solution, though... because eventually there will be no wazers on that route, then it won't know that it's slower.
You'll note that we don't specify the number of lanes when we're editing the map... so the algorithm doesn't care about that.
Also, ultimately, two lanes can have the same speed as six -- as long as the volume of traffic is reduced to one-third.
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