you don't need U-Verse to get HSI.
You can easily order DSL without getting U-Verse. Would you like a list of DSL companies to order that from? Maybe a list of other providers including Earthlink that offers Cable modem services in TWC service areas. Maybe the number to your local Clear office to get service with them? Also there is LTE with Cellco.
Those are options. Just because you think that TWC is your only option due to you wanting to have Tivo does not work with your HSI claim.
Yes, I can order DSL or wireless, get lower speeds, less reliability (IMHO, but that's subjective), pay a bit less for that, more for my TV service with the bundle gone, and come out with less for about the same price. Sign me up.
The whole package (TV + HSI) is what matters, not one or the other. The Tivo issue is relevant simply because it limits the TV choices to maintain that investment to one company, which affects the pricing for the combination of the two.
Is it a self-inflicted monopoly? Sure, in a sense. But Verizon's FIOS works with cable cards, so there are markets where that competition exists, and this isn't one.