Well, as a final argument I would ask you look into any hobby or commercial or industrial machine shop on any scale and note the complete absence of these vices

Well, as a final argument I would ask you look into any hobby or commercial or industrial machine shop on any scale and note the complete absence of these vices, despite the original patent being issued 100 years ago. I use strap clamps on a hobby mill to hold steel while being machined, they are plenty rigid.