I wonder why this kind of screws are not more popular? Is it really that much harder to produce them or there is some other reason for not being used everywhere? You can use them either with flathead or Phillips head screwdriver, looks like win-win solution?
P. L. Robertson invented the Robertson screw and screwdriver in 1906 and received the Canadian patent in 1907 (CA103387, U.S. patent CA103387A) and US patent in 1911 (U.S. patent 1,003,657) for a manufacturing machine. The cold forming was a separate patent.
Roberston refused to license to the US and Henry Ford because Ford was being a dick.