Aside from the major efforts in sprinting or bunnyhopping, I agree that a casual rider wouldn't gain much benefit from a clipless pedal. The test only looks at the "normal" pedal stroke common for most of our riding, so this doesn't surprise me much. I believe the bigger issue for the platform pedals is the placement of the foot on the pedal. If the foot doesn't sit in the proper position fore/aft, or the rider tends to twist their foot/knees during the stoke this could potentially lead to problems. Over a 50+ mile ride this may be more pronounced as the rider gets more tired and sloppy. To me, its not so much about the efficiency of the pedal stroke, but keeping the foot in the proper place without having to think about it.