And just how do you think that multiple drives could be used to create one big space without either software (shiver) or hardware RAID?
Easy to do on the SD TiVos. No RAID required. I think the reason the HDDs are not added together is that D* doesn't want everyone opening the boxes. There is plenty of room in the boxes for an extra bracket that would hold a drive that would couple with the internal drive as the TiVos did. That said, I could care less about the internal drive being wasted. 2TBs of capacity is more than enough for anybody who is not interested in recording every show on TV. I think.