The ground measurement was the slowest part of every iteration: the game ran until the shell's timeout because nothing told it to stop. -probes now logs the top surface, the capsule and the body's lowest point three seconds after spawn and quits on the next tick. A run went from minutes to 13.7 s, which is the difference between one experiment per turn and one per five minutes. Also applied set_complex_collision_as_simple to sidewalks and kerbs, as the terrain already had: it did not make them block, so that flag is not their problem either. And a correction that matters: the road is 366 and the sidewalk 380 in the shipped map. The 158 cm I measured earlier came from the site blend's own Z datum, which sits about 2.2 m below the map's because the terrain was added after that blend was written. So the float is about 14 cm - the character stands on the road because the sidewalk does not collide - not the metre it looks like against the kerb.
57 KiBLFS
57 KiBLFS