As you note, the presentation linkbase is context-agnostic. From the exhibits themselves, there is no explicit way to know which numbers were actually printed on the Income Statement and which facts using the same element/concept are from other schedules.
The SEC uses programmatic means to determine what will be rendered where in its Pre-Viewer and Viewer; they explain some of that in their FAQs and Interpretations (see, for example, question B.3 at http://www.sec.gov/spotlight/xbrl/staff-interps.shtml). They look at key words and phrases.
The SEC makes the source code to their rendering engine available at http://www.sec.gov/spotlight/xbrl/viewers.shtml - you may be able to leverage it or find other hints of how they determine what to print and when.
XBRL was not designed to recreate the original presentation; later developments including Inline XBRL and the new Table Linkbase do more to preserve presentation placement.