If only Congress would allow Amtrak the attitude to do things like this.
Amtrak can do this on the state supported corridor routes, provided, of course, that the state DOT is willing to agree to an aggressive price scheme. And the state politicians & legislatures don't get up in arms about the subsidy for a $1 lowball ticket.
Where Congress blocks Amtrak from bus-buster or airfare-buster pricing strategies are the NEC and LD trains, I think it would be interesting to see what Amtrak could do with a selection of really low ball fares on the NEC for the off-off peak trains and low ridership segments of NEC trips running at odd hours. Extend all the NE Regionals to 9 to 10 cars (if there are enough Amfleets available) and try out an aggressive price strategy to fill the seats with the goal of a net increase in total revenue, Don't have to drop to $1 seats, but why not some $20 WAS to NYP tickets for a 3 or 4:30 AM departures from WAS? OTOH, this could get politically complicated if Amtrak were to sell lowball price seats on some short segments at a price below the competing commuter trains.