Re: Rail washers

The whole flange lubrication concept is still a hot topic on modern railroads.
Many of the Class 1 engines are equipped with automatic flange lubricators. These are activated primarily on curves to limit wheel wear and friction. There were some benefits shown in reducing trailing train resistance even on tangent track. One system uses oil, the other grease. I'm not aware of the current thinking on this regarding cost/benefit.
There is also a "dry" flange lubricator that uses a spring loaded graphited block against the flange on locomotives.
Regardless of the lubricant; its value is on the wheel flange and/or gauge side of the rail. Anything on top of the rail or wheel tread just causes problems.