Don't know where you read that article, but please share it...
Runners are often made of hardenable stainless, 440C being most common in the US. Specialty runners are also common in 316 and sometimes 304. These softer materials work well in snow and slush.
Not to say these wouldn't be great, but it is hard to experiment with expensive components in the limited time we have to sail and when we have a good solution.
Criteria for the perfect material: sharpenable, will easily polish, ductile (resists cracking), hard (resists wear, holds an edge), machineable, available, and steel alloy (not nickel or cobalt or titanium, DN rules), corrosion resistant, doesn't warp when heated, low friction on ice, cheap, available in many T-shapes, angles, plate and bar thicknesses to 0.27 inches
Common solutions: Mild steel (cheapest), spring steel, tool steel (Sarns), austinitic stainless (316), martensitic stainless (440C) (Sherry product)
See
http://www.materialsengineer.com/E-Stainless-Steel.htm or
http://www.alleghenytechnologies.com/ludlum/pages/products/xq/asp/G.11/qx/ProductLine.html or
http://www.alleghenytechnologies.com/ludlum/pages/products/xq/asp/G.4/qx/ProductLine.htmlfor some background on stainless.