So, dns blocking will always block the requests to things on the block list, which includes ads… however I’ve noticed that a many sites are now using js to detect images that don’t load before calling the “full the body with text” api call. Originally this would just do some fancy css hiding of the content so SEO scraping would still work (and oh can just use reader view), but now I’ve seen them pull the first paragraph and then, if the images loaded (or an additional call to a tracking pixel for instance) it would also call to their API to get the remainder of the content.

The other way it’ll fail is if they use the same server/dns hostname for content as they do for ads.