Just looked at the website, I can see how it works but I have never used one.
I can also see the issue that would exist in trying to use it.
1. If you need to change the angle of the skew blade to the wood. For example to plane over a knot or overcome ripple.
2. It would be in the way if you were going from planing to rolling beads. Yeas I can see it is only a captive grub screw but it would be a pain to keep putting on/taking off.
However, I can see that as an aid to learners, to understand the process of plaining wood, it may have some use, but I would not want to become dependant upon it.