You guys sound like you know the nuts and bolts of this better than me but let me offer a story. I was contacted by a home owner that had Direct TV installed and the installer ran sloppy cables and ruined a very expensive vinyl siding. I was contracted to repair the siding and have the wire re-routed. In investigating the need for all the extra cables I discovered this multi-switch and was simply able to use the existing in house cable lines. Each location has an independent DVR. The Owner was furious with DirectTV. The installer was adamant he had 2 run 2 cables to each installation. In my opinion they could have sold the multi-switch to the Owner during install but from what I understand the installer is an independent contractor working on a fixed per Diem. Running 2 wires gets him in and out quicker. Installing the multi-switch would have required a return trip, one that he may or may not have been paid for.
Just be cautious, it was a very sloppy (and expensive) install.
Here's the site for the switch that could have saved a lot of aggravation if installed initially:
http://www.weaknees.com/swm-directv.php
The support at the site may help you with your question.
The Owner reports no issues with the switch and multiple HD TV's and DVRs.
