Well, I finally pulled the trigger. HR-44 was installed today! And yes, I now have 17 working tuners!
The Multiband technician was probably one of the best I have ever had in my house. When he got here with the Genie, I told him that it would put me up to 17 tuners.
After looking troubled for a minute and going through my setup, he told me that he could trade out one of the DVRs for a mini-Genie, or he could disable one of the tuners on one of the DVRs. He said that I would need a SWM-32 and Directv was not supplying those. I asked him about cascading SWM-16s, and he said that the only problem would be that I wouldn't be able to share playlists across the 2 SWM modules. I said that I would rather do that than trade in a DVR or disable a tuner. I thought it would be better to install the additional SWM-16 and coax now, because if I wanted to, I could always go back myself and disable a tuner and put everything back on the one SWM-16.
He had to call the office and get approval. He did this, and installed the additional SWM-16, ran wires through my attic to my distribution panel, and I am now good to go. Had some minor problems along the way, but nothing that wasn't resolved quickly. Biggest problem was that the one DVR on the new SWM-16 wasn't getting satelite signal at first. Then he realized that he needed to run power to the new SWM.
So far, I am liking the HR-44. Only been a couple of hours. We'll see how the family likes the speed and extra tuners.
One more question for now - Can I share playlists across the 2 SWM-16s? I have a wired CCK that the installer left connected to the SWM group with my Genie. If I use the CCK to connect the non-Genie SWM group to my network and the HR-44 to connect the Genie SWM group to my network, will they see each other and be able to share playlists?
Thanks for everyone's help!