Parallel stories in "The Passing of Grandison"

In "The Passing of Grandison," Chestnutt tells two stories, that of white Dick Owens and that of Grandison the slave. Grandison's story is deliberately understated and downplayed, with the plot twist at the end of course that he escapes on his own. This structure directly communicated the stratification and separation slavery constructed between races. From the beginning, what to Grandison was a matter of life, death and personal liberty was merely Dick trying to impress a woman (p. 83). 

Chestnutt's irony was particularly biting in the passage on page 88 when Grandison expresses exaggerated fear at the idea of abolitionists, which his master tries to warn him against him: "'Dey won't try her steal me, will day, marster?' asked the negro, with sudden alarm." Over the course of the story, Dick shows Grandison essentially what he needs to do to escape Dick's father and find freedom. Grandison seems loyal to the point of perhaps stupidity to the colonel and Dick, but to the reader it seems like Grandison was acting and biding his time from the start.