In "Gumption", dialogue is used in a way that creates realistic characters, but, in "The secret life of Walter Mitty", dialogue is often used to contrast reality and imagined events.
In "Gumption," dialogue is used so that it speeds the plot along, while in "The secret life of Walter Mitty", dialogue is used to create kind of a "horror" sense.
In "Gumption", dialogue is used to show progress in the natural world, while in "The secret life of Walter Mitty," dialogue is used for the viewer to contrast reality and imagined events.
Gumption uses dialogue to create realistic characters, but, in "The secret life of Walter Mitty," dialogue is used to demonstrate correct grammar.