Say there is a gallery where every painting has no attribution to the artist. In its place, the person who made the frame for the painting is given credit. Even if the frame lends much of its power from the painting, the gallery decides that the viewing public should know of the frame maker only.
In improvisation based music, those who create the tune or the guidelines for musicians is given compositional credit. In some sense they are the frame makers. Those musicians that add the color and richness of improvisation to these frames often go unattributed or listed as a performer and not a creative contributor.
Andrew Durkin, who inspired much of these thoughts, has written about this issue in his book Decomposition: A Music Manifesto. He writes that “[i]mprovisation is more often than not the real point of such music, adding a good deal of content that wasn’t there in the first place – including not only new melodic ideas but variations on the harmony and even form of a pice. Yet for all its aesthetic impact, none of this is typically recognized as compositional”. Even if the frame is made for the painting, the frame maker is only recognized.
There are also plenty of times when the painter is given credit over the framer. Some jazz numbers are known by the performer rather than the person who wrote it. It makes one wonder whether the delineation between a composer and performer is even as easy as a frame and a painting. Compositional credit might not even be the point.
Maybe messiness is the point.