I have Qwest VDSL (Motorola branded RG2200C). I have three streams.
I haven't found a way to let my #2 Tivo control the VDSL gateway box, but all is not lost. You can schedule timers on the individual streams. I just do it when needed to get around scheduling conflicts.
I don't know if it's an option for you, but you might concider and ATSC tuner for the #2 box. This will let you have full control for recording network television if it's an option for you.
I have the VDSL gateway and an ATSC tuner on the #1 Tivo, a VCR to translate channel 7 (stream 2) to channel 4 to get stream 2 to Tivo #2. This Tivo also has an ATSC tuner. Tivo #3 is connected to my 4DTV.
Since setting up the ATSC tuners I almost never record from the #2 stream. Tivo #1 does the bulk of my 'off cable' recording.
The Tivo is limited to channels 3 & 4 so you'll likely need to use an old VCR to tune in one of the alternate streams as well.
If I was doing it over I wouldn't bother trying to get stream 2 recordable. It is more of a pain than I think it's worth. If it's your only option, go for it.
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