Whats on your turntable tonight?

That is correct. There is still an arc however (minimized due to the 12" tubes) as it doesn't have a cam to keep the pivot on a straight line. The cam idea is actually something I've toyed around with prototyping but there is a MULTITUDE of hurdles to overcome in order for it to work properly. Not sure if Thales is a true linear track or not. It just might be. 

Genesis / Lamb lies down on Broadway 

Does this design put more stress on a cartridge/cantilever/stylus?

Less actually because the tip is always aligned with the groove. 

I need to actually investigate. I can’t, at the moment figure out what causes the stylus to stay parallel "in the groove" without the VTF pressure on the stylus being the mainstay that causes the rods to adjust to the stylus tracing a record groove.

Graham Parker "The Mona Lisa’s Sister" RCA/1988