A friend once told me how torrenting works. Someone puts up a movie and a person downloads said movie. When another person downloads that movie, she does not get it just from the first person but gets bits of the movie file from both the first and second person. Repeat this process and this person receives the movie from components of the first, second, and third person. Now imagine this process done thousands of times over.
That is why it is so difficult to single out an individual and indict him as he who put up an illegal torrent. When a first mover is proposed, other sources are revealed to make up that file. This could lead one on a seemingly endless or at least exhaustive search.
In the case of music, we try to pin down an origin of a style in an certain artist. Such and such composer embodies such and such style. Though if we take up the torrenting analogy, it might be more difficult than we think to label a first mover of a style. That musician might have took a good part of what they have from countless other artists who then took their characteristics from, again, countless others.
What could this mean? Possibly that instead of trying to find first movers of musical ideas, we should be concerned of the network of connections that a genre or time in musical history projected. Even musical theory ideas like chromaticism could be explored in tandem with musical history, exploring the various torrents of said idea.
Worrying about a composer individually is paramount, but music does not exist in a vacuum. Maybe it exists in a torrent.