Yes, if I downgrade to PiTool 1.0.1.253 or 1.0.1.254A, everything works fine. The issue only appears in PiTool 1.0.1.255 or later (and is present up to the most recent version 1.0.1.262).
It’s fine in the config tool (i.e. the pose tracking follows my head position smoothly). Similarly, it works fine in earlier versions of PiTool, so I don’t think it’s an issue with the tracking in PSMoveService.