20$ a day for a commute is going to block the people that would benefit the most. Only middle and upper middle class people will be able to afford it.
Could see it making an effect on marginal[0] decisions (like buying a second car as you state) but it still sounds more to me like being used more for one off trips than for commuting. It's far to expensive for that.
[0] marginal in the economic sense
Your best bet, as a new rail line are people whose regular transportation demands change while the line is still new and shiny (e.g. new job at the far end of the line, do I drive/move/rail?). This also meshes very well with the real estate development model of financing the line.
Plus ~12,000 fewer miles driven per year. Even if they can't get rid of their car payment/car insurance entirely the mileage saved is significant.
This was cars sold in 2012, so only 6 years old. The average light vehicle is almost 12 years old. But according to some reports, the measurements in the US are different, leading to lower MPGs for the same car.
I guess my messed up reasoning when I am reading a sentence...
$ = dollar
20$ = Twenty Dollar
$20 = Dollar Twenty
I know it's not the correct way but it's the way my mind thinks...