Nice thread! What I’ve found out in 4.12 is if you use AttachActorToComponent and LateUpdate with controllers, the moment you detach actor from the MotionController component (resuming physics simulation) you get a funky lag/jump-in as it stops the LateUpdate.
Didn’t find the solution for this - apart from disabling LateUpdate for the MotionController, but then you get a visible lag when you compare controllers position with SteamVR overlay…