I agree with Close first hypothesis was that being a gift isn’t just a gift. It’s more than that.
The meaning of athletic ability exist in inverse proportion to intelligence is that you have an ability like an athlete and you you that to make smart decisions.
The expression you’ve been riding the gravy train longer means that you have been on the road longer than you think.
In "The Notorious Jumping From of Calaveras County" by Mark Twain, the shortcomings that the narrator and Jim Smiley share was they were being greedy. Jim Smiley is the main character and showed his greed for money but got in trouble.