Have you  read each of the adjoining patents?  Your assumptions are possibly in error.  ARRC has the engineering completed in 1923 though their trains go faster, heavier, and longer.  Some of their curves adjoin mean high tidelines which were given at statehood to the people of Alaska to go upon and  rely upon forever.  Some corners following a meandering tide line drawn by nature that make a mockery of the linear mythology of an exact 200 foot measurement.  The actual meander as authenticated by expensive tideland US recorded BLM surveys which it is illegal to obliterate.  So, ARRC owns to the point where the soil is tidally affected and gets wet.  You may have tidelands filled to the moon but they remain forever tidelands which were given to the people of the state of Alaska irrevocably in 1959 if one believes that. In some places there may be only 15 feet from the 1923 engineered bed.  So that is all they have regardless of speeds of 1920's or 45 mph in 2016.  New design time.