Centos and erasures are two of my favorite forms, and I use epigraphs and ghost lines. Yes, they draw upon others’ materials for both text and inspiration, but they give credit and what is created is (and should be) something unique. After a recent incident of serial plagiarism—which seems to be outright theft from several poets—and cultural/personal appropriation, these forms and poems that clearly draw inspiration off of other writers seem tainted.
I believe there is a place for these forms and for conversations among poems and between poets within works, BUT attribution is required. I don’t ever condone or promote plagiarism. Yes, poets imitate poets they admire. I have been to readings in which younger poets’ cadences and imagery were clearly influenced by a poetry idol within their community. Much of this imitation is unconscious and an indication of admiration and learning, but the poets were clearly writing their own poems.
Developing one’s voice can be a long process—I am still developing mine, but the centos that I have created do seem to have what I consider my voice. I am very careful to note the origin of each line. If you do create a cento or use a line for an epigraph or consciously structure a poem after another, give credit and ensure your poem is not just a copy. If in doubt, ask someone to look over it. If the poem seems nothing more than a replica or an echo of the other poet, put the poem aside. Come back to it when you have a clearer sense of your own voice. Be good to the community and to yourself.
I welcome hearing your viewpoints on these forms. Best wishes and good luck writing!