So, fun stuff.
Even blocking the mm1, the ribbons stayed in my guide.
However, I did discover that blocking this stuff can interfere with your TTG functionality, if you like to transfer/download/use a program like KMTTG to transfer non-DRMed shows.
I spent hours trying to figure out why suddenly KMTTG was claiming ALL my OTA stuff was DRMed. Turns out that if your boxes can't connect to TiVo, they disable that functionality. So you have to unblock everything and go back into your account and re-enable downloading/sharing:
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Which means you may also have to adjust your TiVo privacy settings:
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Because your preferences can't be updated if you've "opted out" of tracking/advertising.
I made the mistake of initially accepting the TiVo+ ToS, so maybe that has an effect of why it seems more persistent on one device compared to the other.
I'm going to call TiVo back and try and ask that the ads be removed again, since they never went away as stated. Humorously the last time I was trying to describe how TiVo+ crashes the device it happened while I was on the phone with the agent (they apparently can't see any logs though, since I was hoping that would prove the trouble I'm having).
If the next call doesn't resolve anything, I'll go back to TE3. It was fun for a brief moment to mess around with this stuff, but it's definitely entering more trouble than it's worth territory now.
One thing I did discover is that the TiVo+ content is provided by Xumo, so blocking the xumo.com domain at least keeps TiVo+ from launching, although it doesn't affect the ads or guide. But if you're like me and accidentally starting the TiVo+ channels from the guide leads to a hard reset, it may be worth avoiding that, at least.