Is changing an employee’s role too fast and too often legally dangerous?

Q: “Our company has changed an employee’s position four times in one year and his title twice in the same year. He was the assistant scheduler, scheduler, shipping/logistics admin, and his latest title/position is customer service rep. Other than the move to shipping/logistics admin, none of the changes were welcomed by the employee. None of the changes produced job descriptions or expectations. Basically, he shows up and is told that his office and job have changed. Lacking an up-to-date employee handbook, what are the legal ramifications should he choose to file an EEOC claim?” – Anonymous, Texas