If you have ever tried to groove with a table saw you will have noticed that it is not at all easy to adjust the width by making the cut in several passes. If we could reduce the number of passes we need to make we would certainly achieve greater accuracy, so it would be good to have some sort of given set of blades for slotting. According to Matthias, they are banned in Europe (I really don’t know how the issue really is), and what is certain is that they will not be cheap.
One option might be to put two or three normal blades next to each other, but if we go back to the issue that saw blades are banned in Europe for this type of cutting, I guess we are just feeding our fears…. This sounds dangerous! The truth is that after reading your article I would say that Matthias is quite comfortable with this system and takes the heat off the issue.
For me personally, one of the things that scares me is that the blades will come loose, although I think the bolt on my saw is long enough to safely tighten two or three blades together. In addition, the machine rotates in a direction in which the force on the screw is in the direction of tightening, so I see it difficult to loosen it. And another thing that scares me is whether this would increase the possibility of the dreaded kickback, although when gouging with the table saw we tend to be more careful than when performing other types of cutting.
As always you have the link to this Woodgears article in the woodworking projects tab of this blog, and there go to woodgears translations (#19).