"Waldo" wrote in message
.. .

Not true. Robertson screws have been used in Canada for well
over sixty years. Apparently Henry Ford was interested in
them for his assembly line but wanted full and exclusive
ownership of the design. Robertson, the inventor, would not
go for that and as a consequence Ford declined to use them.
Then along came the Phillips design and it became the
American sweetheart because it was invented by an American
and was somewhat superior to the common slotted screw.

Somewhat? Ever try to start a slotted head wood screw without a pilot hole?
With a power driver? With one hand? Every slotted head screw I come across
is scrapped. I don't have ONE to my name.