Allow me to shed some light. I am a sound engineer who has worked for a band that appeared on SNL and have mixed on every late night show (except the Tonight Show and the new Conan show). Basically, the bands regular live sound engineer is allowed to “produce” and “direct” the broadcast engineer (supplied by NBC…a full time position, and one with a massive background in recording studios). However, according to union laws, visiting engineers can not physically touch the console. Now, in every late night television show I’ve been a visiting engineer, I’ve been able to handle the faders on the console for any special effects or cues within the song. STILL, I can not physically mix the taping. HOWEVER every broadcast engineer, with the exception of one, allowed me to freely direct and also took notes from the artist after the taping was complete (and note they are not required to do this but as a whole, these are very generous people).

What the audience hears is the mix as engineered by a professional but produced by the bands engineer. Without experience, a live engineer can produce the mix completely wrong, make it sound completely dry, and it will sound shitty coming out of your television and laptop speakers. I am afraid the blame would fall on the visiting engineer more so than the broadcast engineer. But that is just my humble opinion.