It’s not easy to catch. They could add a layer dedicated to checking authenticity, but the times you suspect are, eg, when writing in the CA essay out shines that in the rest. (But how do you spot if a 3rd party wrote the whole app?) I disagree this is about intuition, per se. You have to deal with what you do get in an app pkg. There isn’t a lot of time, eg, to contact every GC about ECs or go looking at Max Prep or local newspaper reports of All State athletes, even if it were just finalists.
In an interview, sure, we all get a sense of who’s genuine, even if flawed, versus an an Eddie Haskell. But that generally depends on alum interviewers. On CC, we see posters respond with some suspicion, when kids seem bogus, overinflating accomplishments, asking dodo questions, etc. But we don’t know.
Maybe the CA needs to ask GCs to list ECs? Some do now, but even so, they make mistakes. And do you trust them to verify out of school activities? And not all GCs have time, either .