Hmm, I don’t think it is exclusivly the normals at the edge of the terrain causing the problem (I get similar issues on brush/spline seams) - but it may well make it worse.
Regardless - an extra layer of sunken vertices around the edge of a terrain segment should really reduce the issue - but I’ll probably leave it unless someone actively expresses interest.
Yes - tempted to switch to rt/sweep after discovering other places where collisions do not work quite as desired - though, may try some other ideas first, perhaps increasing number of substeps even more, or something I’ve not yet thought of 