Ok so we are talking about the same thing. Your right, it's all relative. The ocean could be moving at 50 knots and you wouldn't know it unless you looked at land. I wasn't quite getting the boat in bucket idea but know i see what you were trying to explain. I guess i was just trying to say is in the open water, you want to go point A to point B without leaving a straight line. Daggerboards help accomplish this by minimize side slip. In a channel, you would want to maximize side slip to help you get up the channel by letting more water flow under your hulls sideways than streaming past them. This idea only works when the wind is at your back. Does this make anymore sense? We are taking about the same thing but different aspects i think.