Unable to Relate to Skillet and Fode

Upon reading Relating to Skillet and Fode, I had no clue as to what was going on in the story...at least what was supposed to be humorous. With nothing to write on the humorous aspect of the story, there is none, I did some background research to understand what message Percy was trying to get across.
I still have no idea what he was writing about. I checked out his page on Wikipedia, and was surprised to see that Percy, though the son of plantation-owning U.S. Senator, conversed regularly with Harlem poet Langston Hughes and others of the Harlem Renaissance. All I could really appreciate about Skillet and Fode is the kind disposition Percy had toward Skillet, a black-boy he played with in his youth, and Ford, his worker/companion during his older years. The dialogue between Ford and Percy is not necessarily what one would expect between a black man and a white man during the early 20th century. Though racial tensions ran high in the south during this period, and still decades later, the two carry on like good time friends. Ford, able to call Percy a "little old fat man" and Percy with a sub-par comeback of "You damn fool". That Percy could see beyone Ford's color during these times is something to admire.
Let's be honest, there is absolutely no point to any of the stories Ford tells to Percy when the two are overlooking a river. As a 22 year old in the 21st century, I find no deep meaning to any of the stories Ford tells. It appears that neither does Percy, remarking that the second story Ford tells him is "just as inconsequential" as the first. Perhaps someone of these times could find meaning: A former slave, a slave owner, a white or black man living in the south at the times.
It was only through discussing the story in class that I understood the meaning of "Martin" in the second, inconsequential story. The point being that the "negro" man kept waiting around in the scary house, peering at the cats in front of him. Getting bigger and bigger as they come, the biggest cat says something to the point of "we aint goin do nutin til Martin comes." Who is Martin? A literary reference, also used in Twain's Roughing It, to describe a person who evokes fear even in the biggest of men, or in this case cats. Although the story then made sense, once understanding the meaning of Martin, it still didn't seem to have any meaning to the overall story.
If I had to struggle to find humor within this story, which I will do, I will say that when the black workers jestered that Percy's car is actually theirs, because it is THEIR work that payed for his car, and that Percy is initially unaware of their observation, the dramatic irony does work somewhat to produce a smile, but not much more.
The third story, of a black man who puts off work he promised to a white man, only to be told by a cooter that he "talks too much" isn't so much funny as it is a prophecy. Should the black man have said nothing about the cooter, he wouldn't have receive the whooping from the white man once the cooter did not speak in the white man's presence. Hence, the black man should have said nothing, but couldnt, because, as the cooter says, "nigger, I tole you you talks too much."
Should I have been alive during the early 1900s, or have been familiar with "negro stories", perhaps I could have found something to relate to within this entirely irrelvant story. But with no lense within which to view this story, Skillet and Fode failed to make an impression on me.