Regarding this popular issue (new to me) about slowing down when approaching the crest of a hill:
In theory any hill-crest can be a "blind hill" if you know nothing about the topography of the road that lies beyond it. It always
could be a sharp drop into a local valley that could hide a stopped or oncoming car, big boulder or other hazard.
Obviously such blind hills do exist. However they're rare, it's well-understood to be dangerous and it merits a warning sign, light, speed-bump or other hazard mitigation.
In actuality, the sight horizon over a hill-crest is part of standard road engineering practice and is based on standard geometry assumptions. For any human looking over a dashboard, the eye height above the road surface is usually taken to be at least 4ft ≈ 1.2m, perhaps a bit less for especially low cars. The height of hazardous debris is sometimes taken as 6" ≈ 15cm; of course stopped or oncoming vehicles are much taller. These assumptions along with (real) traffic speed and cconservative reaction+stopping distance values, and the possibility of oncoming passing-maneuver traffic in the driving lane, all govern the acceptable crest profile to avoid a "blind hill" hazard.
So. if Tesla AP is braking abnormally upon approaching a crest in the road, it suggests one of two things:
- Tesla driving decision policy is being quite overcautious in assuming a very unlikely road-design failure. As we know such over-caution, leading to unexpected braking, is itself a traffic hazard.
- This concern BTW can be mitigated by using the elevation data in established navigation maps. I don't know whether maps are typically marked with dangerous blind- locations, but said elevation topography data could be used to create such markers.
- Tesla is not being purposefully over-cautious, but the problem is it cannot confidently determine the distance to the crest, and it interprets this as a possible rare blind-hill scenario for traffic coming the other way over the crest.
Given all of the above, my conclusion is that this is a very solvable issue as long as Tesla Vision can basically see. Unlike the pillar-camera situation, here I'm not seeing a fundamental geometry problem with the existing perception suite. In fact the forward-looking cameras are sitting higher than the human driver.