Review on 🔴 JoyTube Self Centering Dowelling Jig: Accurate Imperial Dowel Joinery for Woodworking Enthusiasts - Cabinet Hardware Jig (Red) by John Destruction

So the idea here is that the dowel holes are centered on the parallelogram - you hold the workpiece between the two sides of the parallelogram and the dowel holes are automatically centered. Should work right? However, it turned out that the dowel holes on the device that I received were not exactly in the middle. I'm not sure why, but if I hold the workpiece at one end and drill a hole and then hold it at the other end and drill a hole, the two holes don't line up exactly. It turns out they are both off center by about 3/128 inch. So if you have two pieces of equal thickness and drill in each hole the same distance from the same end, flip one over and insert dowels in between. They will eventually be offset by 3/64 of an inch. It could just be an issue with the specific device I received, or it could be a more general issue. I don't know, but this article doesn't suit me.