Social media and television's economic system have given rise to a counterintuitive trend: The more opportunities there are for people to watch TV on their own time with DVRs and video on demand, the more valuable programming that can deliver a big live audience has become.
It's not just stunts. Live sports, awards shows, singing competitions and the Olympics are all examples of programs that networks consider DVR-proof.
"The larger the event, the more buzz-worthy it becomes, the more social it becomes and it breaks through the clutter," said Andy Kubitz, ABC scheduling chief.
Wallenda's walk across Niagara Falls last year was a Top 10 show that week for ABC. An average of 10.7 million people saw him on a tightrope stretched over the Grand Canyon in June — the most-watched live event in Discovery's history.
Watching ruefully from his office was NBC executive Paul Telegdy, whose network partly paid for Wallenda's tightrope. NBC had been planning to air it, but Telegdy said his bosses at the time got cold feet.
"The Voice" and, in particular, the London summer Olympics taught TV executives that social media conversations about programs can create excitement and build a larger audience. That's true of taped programs, but much more so with live events.
Building a big live event was the idea behind "The Million Second Quiz," which NBC aired over two weeks in September. The competition was live, and viewers were encouraged to play along on their tablets at home. The show was a critical failure and didn't meet NBC's commercial expectations, but it still reached more people than the reruns that would otherwise be shown. Telegdy said it's important to take such risks, as NBC will do over the holidays with a live production of "The Sound of Music."
"If somebody has a big, crazy and ambitious idea, they're going to call me before they call other places," he said.
Networks love programming that makes news — a stumbling celebrity on "Dancing With the Stars" or cringe-worthy audition on "American Idol" — to create the aura that people who don't watch live are missing something.
Awards shows are dependable draws, even more so in recent years. Networks try to stretch the experience by making red carpet shows or, in the case of the Grammys, a performance show built around the announcement of nominees.
Sports are becoming more visible in prime-time. NBC's fall schedule flows from its Sunday night NFL game. Saturday night, once the outpost for reruns or "America's Most Wanted" on Fox, is now dominated by football games. Fox is looking forward to airing World Cup soccer.
Scripted dramas can become events of their own with cliffhangers, bold plot twists or special guests. A program that pushes its way into the national conversation — think of the brutal "red wedding" episode of HBO's "Game of Thrones" — is pure gold.
AMC's "Breaking Bad" series finale and "The Walking Dead" season premiere qualified as big events that many people had to see when they first aired. It's ironic, then, that much of their popularity is attributable to delayed viewing by people who discovered the shows on streaming services.
"To be able to put on a program that week in and week out viewers must see that day — that is every broadcast networks' goal," said Dan Harrison, a planning and programming executive at Fox.
Networks don't dismiss people who record shows to watch later; it's just that the business isn't set up to reward that practice. If you record "The Blacklist" and watch Saturday night, the Nielsen company doesn't count you in the calculations that are used to determine how much advertising revenue a show gets. Only people who watch a playback or video file within three days of its airing are counted, and only if they don't fast-forward through commercials. The surest way to be counted is to watch live.
With the three-day limit in mind, CBS has even taken to advertising some programs the day AFTER they air, said David Poltrack, research chief.
Some advertisers pay extra to reach live viewers because they're considered more passionate consumers, or tailor advertising campaigns to live programs.
All contribute to an inescapable fact: "The value of live viewing has gone up," Poltrack said.