Anyone who can bullshit so well they can survive this really ought to be in sales or something. They'd make way more money with their evidently incredibly good social skills, working in a field where it's directly applicable.
I'm convinced most of the "bullshitters" people "catch" with programming puzzles, who "can't even write a for loop" are just choking under interview pressure, or are for-real bullshitters but never would have made it through the process you describe anyway, because they're not that good at bullshitting.
We were interviewing someone that used to work with my manager... as his boss. My manager basically said "This guy is awesome, we'd be crazy not to hire him" but obviously my manager wasn't allowed to be a part of the interview.
He BOMBED the interview, which was a pretty simple coding challenge. I could tell he was incredibly nervous (despite being a very experienced developer) and it felt obvious to me that he was only bombing because he was just so nervous.
I could tell from talking to him that he probably knew what he was doing. We hired him and he was great. Some people are bad at interviewing (myself included.)
I'm convinced most of the "bullshitters" people "catch" with programming puzzles, who "can't even write a for loop" are just choking under interview pressure, or are for-real bullshitters but never would have made it through the process you describe anyway, because they're not that good at bullshitting.