A setup with 1 HR34 and 3 C31s would eliminate the need for any DECA connection (DECA connected to your router) right? You can just plug the HR34 into your router via ethernet and the C31s via coax (SWM LNB, 4 or 8 port splitter) and get OnDemand content on the HR34 that can be viewed and served from the C31s. No wireless connection kits, no wired connection kits, pretty simple right?
That can be done with any setup that has an HR34. AN HR34 and 3 H25s can be set up the same way with the ethernet connected directly to the HR34. The HR34 and all 3 H25s (or H24s) would all have internet connections as well as Whole Home DVR functionality.
DirecTV just doesn't tell the techs that to avoid confusion with the HR24 that can't be set up that way. If you hooked up one HR24 and 3 H25s (or H24s) and hooked up the ethernet connection directly to the HR24 only the HR24 would have an internet connection and Whole Home DVR would no longer work (because the DECA adapter built into the HR24 would shut itself off).