I don't know what happened to this user, but he is onto something which was touched upon back when the lighthouse technology was new. Namely, the ultimate, but expensive, "lightgun" system.
I have my doubts about the accuracy of camera-based VR controller tracking, but the lighthouses are supposedly super precise. All it would take is a VR tracker attached to a gun (something like
this), or a specialized gun with the sensors, and a lighthouse (preferably 2) in front somewhere. It would then know exactly the position of the gun in space, as well as exactly where the barrel is pointing. The only problem is that it wouldn't know where in 3D space the monitor is located. So, this would require an additional sensor for the monitor, or some finicky calibration. But once everything was dialed in, it would probably be pretty amazing.
Hopefully the project is made available and works with those items, as I'd love to give it a proper test.