We teach a great deal of flat water strokes in our river kayak classes, some may wonder why?  First off, flat water is often a very safe place to practice new skills.  Also, many of common strokes used in whitewater are also used in flat water - a great example is the suprisingly challenging forward stroke.  Flat water practice removes additional factors and really enables you to concentrate on good form like torso rotation, reach, padle angle, posture, etc.  When we build up enough speed, we can simulate the effects of moving water and practice our J Leans to carve the boat.  Many of the best world paddlers do a great deal of flat water training.