So if you have a premiere Tivo (S4) and you've WinFS'd your drive to "fix swap" or did the bootpage option1/option2 fix and you find your drive not booting it's because it's overwritten block 0.
The fix here is to get a copy of a good block 0 and overwrite it. This can be done by using iBored and making a VHD of your drive, then re-writing it back to your drive.
At minimum we could see that it was using /dev/hda vs /dev/sda - which is also documented in these forums that /dev/sda was a change in the S4.
All the credit goes to jmbach working thorugh this with me at "odd" hours. I can't thank him enough for his help and hope this fix will help others. There are a few threads in here that discuss this issue.