Short answers, pulled from the story.
Grinding is an abrasive machining process that uses a grinding wheel as a cutting tool. Each grain of abrasive on the wheel acts as a microscopic single-point cutting edge, shearing tiny chips from the workpiece. It can produce very fine surface finishes or remove large volumes of metal rapidly, depending on the operation.
Creep-feed grinding was invented by Edmund and Gerhard Lang in Germany in the late 1950s. It was designed for high rates of material removal rather than surface finishing, with grinding depths up to 6 mm and spindle power requirements of 51 horsepower.
Continuous-dress creep-feed grinding (CDCF) removes one cubic inch of material in 17 seconds. Standard precision grinding requires more than 200 seconds for the same volume, and the original creep-feed process takes 117 seconds.
Standard cylindrical grinding holds tolerances of plus or minus 0.0005 inches for diameter and plus or minus 0.0001 inches for roundness. Precision cylindrical grinding can reach plus or minus 0.00005 inches for diameter and plus or minus 0.00001 inches for roundness.
Peel grinding is a process patented in 1985 under the name Quickpoint by Erwin Junker Maschinenfabrik, GmbH in Nordrach, Germany. It uses a thin superabrasive disk oriented almost parallel to the cylindrical workpiece, operating similarly to a lathe turning tool.
High grinding temperatures can form a thin martensitic layer on the workpiece surface, introducing microcracks that reduce material strength. Grinding also increases susceptibility to corrosion through high surface stress and may cause ferromagnetic materials to lose some of their magnetic properties.