Back in the mid-1970s, when communications satellite links began to replace terrestrial microwave towers and buried coaxial cables for distributing TV network feeds to local stations in the USA, the paradigm of live-transmission (from whatever program streams were originating in each network's master-control room in NYC) continued virtually seamlessly.
Of course by the 1970s, those master-control program streams consisted mainly of the playback of previously created films or tapes rather than actual "live" material, the practise of telecasting "live" dramas, sitcoms, game shows, soap operas, etc. having been largely discontinued in the early 1960s.
Yet the vast majority of network newscasts, in which an anchor/presenter reads a news script (between various pre-recorded story segments) plus sporting events, awards shows (Emmy, Oscar, Tony, etc.) and high-profile "breaking news" coverage (where field correspondents report from the scene in "real time") continued to be done "live," with all the customary hazards of missed cues, wrong camera shots, microphones turned on (or off) at the wrong time, incorrect identifier-titles being superimposed, and playback equipment either jamming or being loaded with the wrong adverts, promos, theme music, or other pre-recorded segments.
And there was also the ever-present risk of an on-camera/on-microphone performer, guest, interviewer, commentator, or interviewee not just missing a cue or reading the wrong line in the script -- but spontaneously SAYING SOMETHING HIGHLY INAPPROPRIATE (usually some prohibited-by-the-FCC obscenity/expletive) that would have embarrasing consequences for the network, necessitate a public apology (for offending sensitive viewers) and possibly even result in an FCC fine being levied on the licensed stations actually owned by the offending network.
The first widely employed means of reducing the "inappropriate comment" risk on live-TV programming was borrowed directly from telephone call-in shows on radio. It was the use of a specially modified tape recorder that continuously played back a loop of tape carrying live-program material recorded at least seven seconds earlier, so that there was a time delay in which a producer could decide to temporarily kill the program signal before it went out on the air, if "something risky" was said.
Adapting this method of "instant censoring" for television was less successful and more failure-prone than for radio, however, since a continuous loop of audio tape could hold up under several hours of use before it started to lose its oxide coating and the sound quality would deteriorate. Videotape was much more delicate, so the networks had to employ a more clumsy method of obtaining the same level of content control that talk radio already enjoyed: stationing two broadcast-quality video recorders (which were as big as upright pianos in the 1970s) next to each other and feeding an entire, hour-long reel of tape (coming out of the recording deck) into the playback deck. And because old-fashioned videotape traveled at at least 15 inches per second, the "slack" build-up necessary to establish even a seven-second delay (between the two machines) had to be temporarily collected in a large basket placed between the recording and playback decks. And if the tape snarled (which it often did) while coming back up out of the basket, the producer had to immediately switch back to a direct transmission of the live program -- or the picture and sound would be lost for the viewers at home. Needless to say, this jury-rigged method of "instant censoring" live-TV programming was only used in the most risk-prone situations, throughout the 1970s and 1980s, even as video tape equipment was becoming smaller and more reliable.
Finally, the arrival of what were called "digital delay" units in the 1990s completely did away with the need for tape-based mechanisms in the "instant censoring" of live television, and by 9/11/01 all the networks (and many local stations too) were fully equipped with them and capable of programming these units (depending on their memory capacity) to delay a live program stream for durations as short as a fraction of a second to an expanse of several hours. Because of the multiple signal paths many network program streams take in the modern era (sometimes involving huge racks of processing circuits and even multiple satellite uplinks and downlinks) these delay units are often used just to keep picture-and-sound "in sync," rather than to guard against inappropriate outbursts -- but their prevalence and widespread use in the TV industry has essentially "done away" with virtually ANYTHING on network TV reaching the viewers as a genuinely "live" stream (meaning that it travels from the point of original performance to the viewers at home at the universal-standard, electrical/vibrational speed of 186,000 miles per second). The next time Obummer speaks to the nation from the Oval Office, try listening to him on several radio and TV receivers (tuned to different stations) at the same time, and you'll see what I mean. Back when Nixon, Ford, Carter, or Reagan addressed the populace, there was only a very slight echo between the various network streams being heard at home in synchronization. Not so anymore.
Well, the point of all this historical/technical digression is that it is entirely possible, and moreover highly plausible, that virtually NOTHING that has come to us from network television, since the 1990s, has been truly "live". Instead, I would postulate that an array of vigilant, trained, and loyal network AND government censors, backed up by banks of digital-delay devices in strategic choke-point locations, has been "riding herd" to make sure that nothing "really inappropriate" reaches the masses via the TV mainstream. Oh yes, there may have been the occasional screw-up, since the human factor is still necessarily involved ("nose-out," anybody... or how about another "wardrobe malfunction?"
) but the level of control is probably quite awesome and intense, and has been for more than a decade.
It won't be too much longer before "they" figure out how to apply it to the Internet too, which means Cass Sunstein's boys won't be needed anymore.