In the late '70s/early '80s, NBC was close to beating CBS for the season-long Sunday NFL ratings. This was a big deal to NBC, because they had the AFC package, where the teams were mostly in smaller cities than the NFC's. The problem was that their main game the last week was a meaningless Jets-Dolphins game, with no real interest to anyone (this was pre-Marino).Would love to give this a go, especially in this no fan moment. Would be cool to hear all the court chatter and coaches for a full game (curses bleeped)
Desperate for a gimmick, the network execs came up with the idea of the "announcer-less" game. Of course, the technology wasn't as good as now, but they did what you suggested: turned up the PA, used more field mikes, increased graphics, etc. Not sure if they ever won the ratings race, but the broadcast got an unbelievable amount of hype.