Originally Posted by DigitalfreakNYC
Please forgive my ignorance but why would you need 2 channels for the same network if they're both the same broadcast format?
In the VH1 Classic example I gave, there are two SD channels to make it easier to find when channel surfing. One channel is located near the other SD music channels, and the other channel is located near the HD music channels, so that HD viewers would see VH1 Classic as they surfed. Then, if VH1 Classic ever began an HD version, it would replace the SD version on the second channel.
Another example is Starz Cinema, whose HD channel is not shown on TWC in NYC. The SD version shows up in two places, once with all the other SD Starz channels, and once with the Starz HD channels, so that HD viewers surfing through Starz will see that there is a Starz Cinema channel that specalizes in independent films, which they otherwise might not have noticed. This then raises the issue of why TWC doesn't show Starz Cinema in HD, which Starz does offer, especially if they're going to allocate a channel number where it should be located!
There are also duplicate basic cable SD channels, which first show up on channels 1-99, and then again as a four-digit channel number. I assume that's to allow one channel (1-99) for those who receive only a basic cable package that only goes up to channel 99, and the other channel (four-digit) is to place it in proximity to other similar channels. For example, CNN will be on channel 30 as part of basic cable, and also on channel 1201, adjacent to all the other news channels, only some of which are also on basic cable. (The HD version of CNN will be channel 201.)