> I can't fathom why it even should. Nonetheless, there were lots of fancy documents and presentations from the WHO and other such organisations explaining this strategy very hopefully.

I can fathom this easily. The general idea is to administer the type 2 oral vaccine (along with 1 and 3, but we’re talking about type 2 here) widely enough that you expect a high level of herd immunity. Specifically, you want sufficient immunity that any newly introduced cases of reverted-to-virulent type 2 will quickly die out. (If you have the resources, you also try to give almost everyone the injectable vaccine to prevent virulent type 2 cases from causing damage). Then you stop giving the type 2 vaccine. If it works, then type 2 is locally eradicated.

Maybe it’s “magical”, but this particular magic has worked in almost the entire world.