[zdkl]

Isn't a risk of encouraging 'pre slowdown' that you might spread the slowdown to conjoining travel axes via lessened throughput per time clogging up intersections or other interface points?

Speaking only as an amateur of traffic manager type games, I see the problem as correctly identifying the repercussions of localised disturbances and I feel that each actor preemptively trying to attenuate jams would merely distribute the throughput problem to the adjoining network. Though the jams themselves might be resorbed, doesn't it stand to reason that (assuming the problem does distribute/diffuse itself) a localised jam may be better than a systemic slowdown? (eg, effect on emergency services, trade...)