Okay, so the Occlusion shader is no more, but there is this tantalizing tidbit in the User Guide:
Exclude Set
A set of groups that will not be affected by GI lighting. If a group is in GI Exclude Set it simply means: this group does not receive GI illumination and nothing more. The group still generates “sky shadows†(occlusions) and it still generates a portion of Reverse Illumination.
However, I can't seem to make this work. If I set up an exclude set I get no occlusion and no GI other than the subtle reverse illumination.
Since there's no longer an occlusion shader, is it still possible to add occlusion to a scene without resorting to a separate manual occlusion pass and a multiplied camera projection?