This design aspect allows the head to make nearly perfect contact with both sides of the hub flange hole. This gives you 1.1 mm more material to contact the flange hole which improves head strength. Good spoke to hub contact is all important because poor contact will cause a spoke head to bend back and forth repeatedly, eventually causing it to snap - always at the worst possible moment of course. Most spoke manufacturers stamp out only a few blanks and then shorten them from the threaded end to create different lengths. Ritchey spokes are forged on blanks made for each length, so that the ratio of butted material to lighter material is uniform for every spoke length.
Spokes are either cold forged or drawn.
Cold forging is stamping or hammering the spoke into shape and a drawn spoke is sort of stretched into shape. Ritchey spokes are cold forged because cold-forging improves the molecular integrity of the metal and keeps the diameter of the spoke center section uniform. This is important especially for lighter spokes because a weak center section can break, and a stretched out spoke can cause truing instability. About spokes in general, using a lighter stainless steel spoke is preferable to titanium, carbon fiber and plastics, in my opinion, because stainless steel affords versatility, dependability and is lower in cost and less temperamental than other materials. As you know, I value high quality components, and use them consistently in building wheels.