He and Jon Stewart keep (kept in the case of Jon) using this excuse when they get things wrong, but when they get things right they take all the glory they can get. The show(s) have to have some sort of accountability.
For example Couric was just ripped for adding 6 seconds of dead air on a documentary....but that's literally what The Daily Show had been doing for years, making people look like idiots (so it fits their segment narrative). That's all good fun until you realize young people think people like Stewart and Oliver are trustworthy news sources.
I like what they do in many cases, but I despise this excuse that it's "just" a comedy show. Maybe NBC nightly news should just add an in-studio audience that laughs and suddenly they can get away with every screw up.