the fragmentation of subjectivity...

...doesn't amount to much if the many voices that say "I" are more or less identical.

They may also be identical in sharing an unreflected-upon, inarticulate comfort with their own contradictoriness--a fragmentation that precedes anything that might happen in the poem.

*

One major problem: "self" or "subject" gets identified with "voice," and a multiplication or fragmentation of subjectivity becomes a matter of multiple voices.

I'd think this problem would have gone away by now, since more interesting solutions were already around by the late nineteenth century.