Since there is a tool for tightening those nuts, there should be a standard for defining the number of knurls? per inch/cm. I googled around looking for such, but didn't find it. I did find the attached document and was amused by the switch picture on page 5.
There is a standard for all knurls.
I ran millions of knurled pieces, of all sizes, on six-spindle screw machines in the 60s.
Some of our biggest orders were for circular saw blade, inserts. The knurl was on the O.D., smooth, reamed, bore at 5/8" on the I.D.