So we should then clarify what the distinction is. I considered Readability to be a typical SaaS app, and now Apple seem to think otherwise.
(Although I appreciate they probably don't use XSLT and I don't mean to demean what they do).
Assuming it is an edge case, then Apple clearly pushed the edge further out to include more apps under the policy rather than interpreting the grey area in the developer's favor. Edge cases set precedent and the one set by Readability may raise reasonable concerns among developers.