Very interesting. I wasn't aware of Father José María Arizmendiarrieta, and your piece is very enlightening.
Especially this:
--Arizmendiarrieta’s manifesto is not done, and perhaps that’s why it could never be penned down on paper. “We should not live cooperativism as if what is accepted and decided at a given moment were something unchangeable,” he said. “Rather, we should admit it as a process of experience in which it is possible and may be necessary to adapt as many modifications as can contribute to cooperativism.”--
One cannot foresee the future, so it's imperative to make amends for that; that is, do not write a manifesto in stone, but rather view it as a template subject to change.
In my novel "The Replicant, the Mole & the Impostor", I do a similar thing. As the uplifted refugees form a virtual nation (the Evolving Nisi Ethicality), they explicitly state in their manifesto:
"These addendums are — like the manifesto and the definitions below — subject to change after evolving insights;"
Great read, many thanks!