The commentary raises an important distinction: syntactic defensibility does not automatically establish clarity. A construction may have a grammatical analysis, yet a succession of unusual placements can make its intended meaning disproportionately hard to recover.
A passage may suffer from weak composition, from verbal obscurity, or sometimes from both.
A sound analysis separates two questions: has a recognized syntactic rule been violated, and has the expression's arrangement made the intended sense needlessly opaque?