I used it in about 2004... It wasn't bad.
Kinda like regular Tube & Fitting, but instead of sleeves you use the 'male' and 'female' sections already built into the tubes ends.
- At one end of the tube (at the bottom) there the 'female' part, which is basically a round internal locking section
- At the other end (at the top) there is the 'male' part, which pokes out with a small lip made to perfectly fit the 'female' part.
Basically instead of using sleeves/spigots to secure your tubes together you simply insert and twist the male part of one tube, into the female part of the other and twist it, until it locks into place.
It works vertically or horizontally.
I also used prefabricated transoms with this system, which were kinda like 'reds/dog-bones' that had a internal pull out section that could be adjusted for either 1 inside board or 2.
I cant remember if this was also part of the Van Thiel System Scaffold or not... - It was a fair time ago, lol.
While i found it easy to use, i think that with those male/female sections it makes it impossible to cut the tubes, which is what helps make tube and fitting so versatile.
I think its the closest type of prefabricated scaffold out there that links the gap between Tube and Fitting and System Scaffold.
EDIT: Here is the link to the -
Van Thiel official site.
Heres basically what it looks like.
I hope this helps.