Vladimir Issurin has praised the American swim coach (Olympic Hall of Fame) James Counsilman for the ideas he used that, to the contrary, resembled the block training system; and Alexander Popov’s coach (Gennadi Touretski) followed block training principles as well.
While it’s clear that linear, concurrent, and block models are all appropriate when used on the right population/sport/trainedness; it is my feeling that at the elite levels of competitive swimming a block model is more logical.
That said, I have a feeling that when you layout the details of your concurrent idea for swimming you will outline more thematic commonalities between your idea and those influenced by block methodology.
I know Pakewi will have insightful comments to share based upon his experience with high level swimmers.