Our town has stopped even the pretense of sweeping it, they just let Spring rain & traffic do the job. Obviously, intersections are the most dangerous. There is a bike road race here in the early summer; they have staff go out to sweep the corners beforehand!
As for your question, what could you really have done? Unless local, you would not know about the debris and the timing of the only 2 vehicles meeting at the apex(?) seems improbably bad.
Maybe this is one of those instances where you did the best you could do?
I do notice both here & other riding forums, as well as in conversation that debris left behind by road/construction crews is a growing theme.
Last summer, I went down on a corner of a dirt road that was slick as snot from the mag chloride they sprayed to hold it solid. I wasn't the only one, either. Happily cruising down the road to ice skating instantly. No signage or warning.
What can you really do? Suffer philosophically...
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