I think they advise not to use ND map modes with negative ACCUR check, that's all there is to it. Kind of make sense.
The strategy you describe seem to have a definition problem because they logically say do not use FMGS generated (using the word "managed") guidance and at the same time ILS to which there are no restricitons also falls into this category (=provided by FMGS) as per quote by Villas.
You'll run into discrepancies like this with FCTM which evolved from a book aptly named Instructor Support. For instance it reads that for predictive WINDSHEAR AHEAD - GO AROUND you should immediately commence the manouevre, wheras FCOM-ABN explains how to ignore spurious warnings.