Edgar Allan Poe presented in five of his tales a hero-adventurer who went into the wilderness accompanied by a black servant and large dog, encountered the threat of a bear-like monster, and emerged from a setting he struggled to describe.
This is, of course, Lewis' June 1805 encounter with the grizzly that chased him into the Missouri and his descriptions of the Great Falls the day before where he struggled to describe the sight and how he "wished for the pencil of Salvator Rosa or the pen of Thompson."
This same image of a fearsome adventurer overcoming all obstacles was used by James Fenimore Cooper and others in their writings as well. He summarized with the thought that Lewis may have become forgotten by history but not by literature.
This is an aspect of the Expedition that has not received much attention, but it may help to explain why the Expedition is remembered as a great adventure story and given much more "greatness" in that regard than what it really was. Let's face it most of the actual work of the Corps of Discovery was very mundane manual labor and recording lists of plants, animals, etc. etc.