I love the use of greyscale filter in "Memento" in order to relay past story elements. The transition to color allows for a very simple, yet effect flashback sequences which do not confuse the audience and also propels scene changes without any jarring or abruptly stopping the flow of the movie. I believe this element would work well in the "detective" portions of the film. Furthermore, I believe that adopting this style of flashback could coincide well with the scene changes from car ride to climax.