There are very practical reasons why the edit is a fundamental unit of film grammar. For one thing, good storytelling generally favors it — few tales demand to be told in real time, without cuts and dissolves to compress the narrative. Conventional filmmaking practice makes good use of the edit by incorporating coverage, the various angles on a scene that allow the film editor some latitude to assemble and disassemble the action. And Eisensteinian montage techniques use the edit to express an idea purely through the juxtaposition of two images.