Originally Posted by stevel
Except when they don't. This forum has lots of reports of "dead TiVos" following power failures. Yes, most of the time it does no harm. But you can significantly lower the risk by taking an extra 30 seconds to have the TiVo restart.
The last sentence is what I regard as unproven.
Yes, there will be lots of dead TiVos following power failures - that's the expected behavior. Upon startup, the Tivo is accessing many critical disk blocks that it never needs to access at any other time, either because they are just needed once, or because they are brought into memory and kept there. Any failure to read such a block will result in system failure.
Once operating, TiVos are remarkably resilient to failing from bad disks. I'm sure many of us have run TiVos for weeks or months that we know have bad disks - we'd never be able to do that with our usual desktops if they were reading/writing disks as much as the TiVo is. Disk failures once the TiVo is operating are much less likely to cause system failures.
I agree that "power bouncing" puts extra stress upon all components, including disks. But I'm not sure it occurs enough to be an important factor in disk life.