Found some Koufax footage. About halfway through this short clip he Ks Mantle, looking, and a bit later, in the dark footage toward the end, is a good strip of him throwing the devastating curve. Note there the emphatic downward motion of his shoulder -- which brought down his hand the faster, which (along with big, flexible hands and fingers) helped him make the ball spin 15 times on the way to the plate instead of the MLB-standard 12-13.
Following up my curveball coverage of last week, faithful reader and Cognitive Daily maestro Dave Munger wrote in noting that Arthur Shapiro, one of the…