"Delineating the Perfect Swim Stroke," by GRETCHEN REYNOLDS, describes the dispute over whether the best stroke is the drag or is the scull.
Here is how the article explains the dispute between the "ancient saints" of swimming and the "House of Counsilman." (It helps if you chant this out loud in a sing-song Talmudic fashion.)
...until Doc Counsilman weighed in, it was widely believed that swimming, for humans, involved primarily drag forces. You pulled against the water, like someone paddling a canoe, your arm remaining straight, palm perpendicular to the body. This stroke technique is often called a “deep catch” style of swimming, since you pull long and deep against the water.We've always decided the Halakhah of the stroke in favor of the House of Counsilman, mainly for the reasons that the article describes.
Coach Counsilman was convinced, however, that lift could and should provide a majority of the propulsion for human swimmers, and that the way to generate lift was to scull, or move the stroking arm through an S-curve underwater...