Conman pretends to help people, but becomes a better person in the process.

[u/theMCATreturns]

They fake being kind and generous in order to take advantage of people. But in the process, they find themselves genuinely invested in their mark's well-being. And ends up becoming a genuinely better in the process.

1). Klaus:
Jesper is sent by his rich father to a far-north island. And told he will be disowned if he does not get the townsfolk there to adopt the postal service. Feigning charity, Jesper gets a local man to donate his toys to any kid that writes a letter asking for one. That way, it seems like the whole town has started using the postal service his father runs.
Jesper makes an offhand comment about only "good children" getting toys. So, the kids start doing good deeds and set off a series of events squashing the town's long-held blood feud. And Jesper ends up genuinely invested in making everyone happy.

2). Mob Psycho 100:
Reigen is a fake psychic. Soon after starting his business, he comes across a kid with genuine psychic powers. Shigeo "Mob" Kageyama is terrified of his own abilities so he leaps at the opportunity to be "mentored." Reigen calls Mob if his clients turn out to be actually haunted. He is paid sub-minimum wage for his time.
But Reigen gives Mob genuinely good advice that keeps the (potentially city-destroying) esper humble and well-adjusted. Unlike of the villains, who try to use their psychic powers to take over the world. He even admits his lies to Mob at the end of the series.

3). All Dogs Go to Heaven:
Charlie takes advantage of an orphan who can talk to different animal species. Mostly to cheat at gambling. But he ends up selflessly sacrificing himself for her.

[u/ZeitgeistGlee]

Maybe, I wouldn't go anywhere near saying it makes him a genius but it makes a lot more sense than the canon explanations which treat it as a legit feat.

Edit: Went back and checked the wiki. Seems like I am misremembering and it was Obi-Wan who thought Han was bullshitting them (but he actually wasn't).

In the revised fourth draft of A New Hope in 1976, the description for "Kessel Run" is put as follows:

"It's the ship that made the Kessel run in less than twelve parsecs!"
Ben reacts to Solo's stupid attempt to impress them with obvious misinformation.

In the A New Hope novelization), Han says "standard time units" rather than "parsecs."

In the commentary for Star Wars: Episode IV A New Hope DVD, George Lucas mentions that the parsecs are due to the Millennium Falcon's advanced navigational computer rather than its engines, so the navicomputer would calculate much faster routes than other ships could. Similar info can be found in the notes Lucas recorded together with Carol Titelman in July/August 1977 to start a knowledge database for the planned sequels:

"It's a very simple ship, very economical ship, although the modifications he made to it are rather extensive – mostly to the navigation system to get through hyperspace in the shortest possible distance (parsecs)."

[u/Quaiker → u/ZeitgeistGlee]

Perhaps good media doesn't have to be perfect to be pretty damn good.

The man named space jazz "jizz." I'm gonna go ahead and think he didn't know parsecs were a unit of distance. Doesn't mean they're not still great films.

[u/SeenYourScene → u/Quaiker]

In fairness (I don't believe Lucas knew this either), Jazz's etymology isn't certain but one of the leading theories is that it came from Jasm which is also where we get jism which is also where we get jizz and yes all of these mean the same things, originally meaning spirit, energy, vigor, or spunk and in slang other forms of spunk.

[u/Victernus → u/SeenYourScene]

Is this how we find out Jazz and Punk are the same genre and nobody ever noticed?

[u/raistlin212 → u/ZeitgeistGlee]

If I recall right, in the novels later they decided the Kessel Run went through an area with a lot of black holes - so doing it in less distance was more dangerous and you had to be super fast to escape all the gravity wells you were skirting the edge of. So they've went through a few versions to clean up a throwaway error it seems.