Definition: Effective playing length is one of the main factors in evaluating golf courses for USGA Course Rating and Slope Rating.
Rather than simply look at the yardage of a course and each hole on it, the USGA rating team comes up with values representing "effective playing length." That means the yardage, but adjusted for the terrain - uphill adds yards, downhill subtracts yards, for example. The slope of a fairway, the positioning of bunkers, forced carries and forced layups, the positioning of trees - all these factors and more go into determing effective playing length.
