Do you think these guys work on this? I used to be an elite swimmer on a private team (USS), high school, and country club. I did little weight training except maybe Bench Press from time to time. (Which really helped my butterfly explosion outta the water). I qualified for Olympic time trials but that was it. My coach was an elite world swimmer who represented the US in various world competitions but we rarely did any serious weight training. I understand many athletes at the level of World Competition probably have more of a training edge than I did or the average athlete does. But swimming is game of maintaining momentum which comes from the legs and core.
I was thinking about KB swings and KB snatches and how they make use of double and sometimes triple leg extension. That power you feel when you extend/snap your hips is a very similar feeling to the extension/snap in the butterfly kick which is used in some way in every stroke. I would think that a swimmer would benefit greatly from KB Leg extension movements. Also, the speed/strength development of arms, back and shoulders from the shrugs and pulls that happen in the snatch and CnJ would be additional great for developing what the swimmer needs to get their hands back ahead of them. (for endurance swimmers- long KB swing/snatch/cnj sessions)
It is given that an athlete can benefit from resistance training of various facets including use of the basic 6 compounds and OLY movements. This is obvious which might make this a moot thread... so this is purely conjecture.