Just because Carson was an accomplished neurosurgeon doesn't mean that he isn't (or couldn't be) a bald-faced liar about his biography or his past. Frankly, who hasn't exaggerated a life story whether it's about the fish that got away or about the hot girl they used to date. And what guy doesn't stretch the truth from time to time in order to impress a woman or to make a good impression. But that's far different from putting it down on paper for publication.
Secondly, IF Carson (or anyone, for that matter) actually told one lie about one part of his life (like being offered a scholarship to West Point), what are the chances of that being the ONLY lie he ever told? I think that's pretty remote, actually.
If I had to guess, Carson probably exaggerated past events in his life for a long period of time.Frankly, I've met a lot of people like that in life. As a general rule, you just listen even if and when you're skeptical about what you're being told. However, if he'd been telling these stories for years, it would look pretty darn strange if he wrote a biography and didn't include those events when he knew friends and colleagues would probably read his book at some point.
Now, here's Carson's REAL problem. If he's lied a lot over the years, the other shoe has yet to fall because he's going to get caught again, and again, and again, if he's told a series of lies. That's little different than how any pattern of behavior can come back to haunt a prospective officeholder whether it's something as serious as repeated corruption or something as minor as serial adultery.
So, here's the bottom line. If Carson had a habit of embellishing his life story and/or self-aggrandizement, the revelations are going to be the equivalent of death by a thousand cuts.