TWIN FALLS, Idaho " The call came as Tom Zuiderveld was driving last month, just minutes from his home on five verdant acres of Southern Idaho's agricultural heartland. It was his district manager, relaying that three of the dairies he sold synthetic oil to had refused to continue working with him.

Zuiderveld felt blindsided " he had known the dairy owners for years, and the accounts represented 80 percent of his income. But it wasn't about his performance, the manager explained on the phone and in a later email. It was about the politics of Zuiderveld's wife.