I am convinced that swimming is both an art and a science and what is ironic is that I have a; er..., "sketchy" stroke and I am about to give an opinion regarding freestyle.
Over at Timed Finals there is an article on Freestyle by Terry Laughlin discussing how to swim with your core. Snippet:
- Consider this… as the core is rotating so that the right shoulder is rising, it is pulling the upper arm along with it. The upper arm is pulling the forearm and hand through the catch. It is NOT the hand that initiates the pull or the propulsion, it is the CORE. If that is the case, should not the kick be timed to assist the core rather than the hand? When the timing is right, not only does the core drive the extensions called arms… it drives the extensions called legs. ALL of the body becomes involved in the stroke if it comes from the core. [Link]
Also noted is that women have proportionately longer legs than men but proportionately shorter arms. That females also have less elongated torsos
With all that in mind, if you compare Janet Evans', Laure Manaudou's, or Kate Ziegler's, stroke to that of Grant Hackett or Ian Thorpe you will notice that there is no Glide phase in these women's strokes but rather constant motion. You will see that they swim with a windmill or kayak stroke whereas Grant or Ian use their longer arms and perhaps core strength to glide.
Subsequently I am convinced that each body type swims in a different way and that no "official technique" can be imposed but rather modified to that person's needs and abilities.
Jazz is a perfect example. Dexter Gordon, Stan Getz and John Coltrane all played the tenor sax. All played with perfect pitch but all have a different sound.