I really like that book but it is still highly unrealistic, since the grid going out != every small electronic circuit being fried. I'm not really clear on the issues with EMPs vs CMEs, but CMEs at least aren't going to induce dangerous voltages on a 5 foot long conductor routed inside a piece of metal (car). For sure not inside a cell phone or wristwatch.

It's more about tripping out the grid, or sensitive inadequately-protected grid-connected electronics. Even then, the short will likely happen in the input stage of the power conversion, where repairs with salvage parts are not infeasible.