Posted by: gjf12 on Nov-08-12 10:23 AM (EST)
If a skeg reduces speed by 20%, you need a new boat. Did you check this with a GPS?
Any motion of your body, or stroke variation for steering, will create inefficiency. Whether this exceeds the skeg drag or not depends on the particular boat and the particular paddler.
One should not use the word 'need' in this context. The question is whether a modicum of efficiency/speed is provided. No kayak should need a skeg in flat water.