Consider Garcia v. SAR Food of Ohio (N.D. Ohio 7/6/15) a cautionary tale.

SAR owns and operates food-court Japanese restaurants. The court previously certified a state-wide collective action for employees who were not paid for post-shift overtime. The named plaintiffs alleged that they were often required to stay past the scheduled end of their shifts, without compensation, to clean or serve expected waves of potential customers. SAR argued that the claims could not proceed because it maintains a policy that requires employees to check their weekly time records, manually enter any changes, and sign off on the records as correct. If the employees had followed that procedure, SAR argued, they would have been paid for all overtime. Indeed, as the court noted, many employees admitted that when they followed this procedure, SAR paid them for the time worked beyond their scheduled shift. [Read More at Workfoce]