I have an idea of what this browser add-on does.
Adobe PDF Browser Control
AKA Adobe Acrobat Sharepoint OpenDocuments Component
AKA PDF Browser Control
Apparently if I disable it PDFs embedded in a page with the <embed> tag fail to function properly.
However, I can't find anywhere accurate documentation on what this add-on below does.
Adobe PDF Link Helper
AKA Adobe PDF Helper for Internet Explorer
AKA AcroIEHelperShim Library
IE9 seems to work flawlessly without it. PDF's still open within the browser with it disabled. Only if I uncheck Display PDF in Browser in Readers preferences does that cease.
So, can someone (hopefully Adobe) entlighten me on what this add-on does, and why I shouldn't just have all employees have this disabled by default?