2 years ago, I got so frustrated at Bob Costas blabbing over parts of the Olympic opening ceremonies that clearly were not meant to be blabbed over that I rush ordered a satellite dish to watch the rest of the Olympics on the CBC.
(Besides, you find out there are events at the Olympics in which Americans are not competing for medals!)
This year Costas was probably a little better, the CBC announcers a touch worse than before but still better than Costas. However, there's an obvious answer out there. Use more text. If you need to explain the symbolism of a piece of music or art, do it in text. Either put text on the main screen, or just put the text into the closed captioning but don't say it.
Another alternative, use the SAP. Have the announcer exercise some judgement, and create one audio stream with just the non-intrusive commentary (during applause and breaks) and add in the blabber on the other channel (probably the main channel since they think the bulk of their audience wants this blabber.)
For those watching in HD, there is much more potential to add text, since you have more screen real estate and can have smaller text and thus more of it.