I dig that we need to ditch daylight savings time, but anyone who suggests that North america could run on two time zones has never done any long distance travelling on the ground, or been at the edge of a time zone.
Getting to work at 9:00 and everything still being dark is ridiculous, especially when for other people in your same time zone the sun has been up for at least an hour ( a problem which is exacerbated the further north you go). I understand that with the advent of electric light, the graveyard shift, and the internet, that time is more flexible and one does not need to get up for a regular 9-5 per se. However we do have to acknowledge that many humans still run on a "get up when the sun rises and go to sleep soon after it sets" model of existence.
The author even cites an example where the Spanish believe being out of time with the sun (being in Central European time as opposed to Greensich-Mean) affects their productivity negatively. And yet, this is exactly what she is suggesting for the people of the Central and Pacific Time Zones. So, why do as she suggests, considering there is a likely business disadvantage in productivity for any productivity that might be gained by having fewer time zones.