however from TFA
"By contrast, the FT points out that it takes the US's Amtrak Acela Express three and a half hours to traverse the 300km from Boston to New York City - although that train has hit 217kph (135mph) in time trials."
So thats an average of 186 / 3.5 = 53 mph!
70 mph (110 km/h) average
and also says:
Distance travelled: 456 mi (734 km)
Average journey time 7 hours
Which works out at 65mph!
The Acela Express cuts the Boston - New York run to 3:23 (from 4 to 5 hours), and the New York to Washington run (the territory of Amtrak's 125 mph Metroliners until the introduction of Acela) to 2:45 from three hours.
Please reset your normality signal. Over.