Scott and Dan,
There are lots of reasons why a survivor might do the kinds of things we see in Scott's poem; figuring out which reason(s) applies in the case of any one of us would be something to deal with in therapy.
If you have closed down entirely and feel nothing, cutting can be a way of feeling something. If as a boy you felt abuse as a total loss of control, then cutting can restore a temporary sense of control; the survivor himself decides if he will cut, when, where, how much, and so on. Or if a survivor feels guilty and thinks he deserves to be punished, cutting can be a way of achieving some sense of resolution or closure.
The problem is that whatever sense of relief the survivor gets is only temporary. Afterwards he is likely to feel ashamed or guilty about what he has done, which starts the cycle all over again.
I really do think things like this need to be approached in therapy. A good T can help us identify the problem at the root of our behavior and eliminate the issue that causes us to cut in the first place.
Nobody living can ever stop me
As I go walking my freedom highway.
Nobody living can make me turn back:
This land was made for you and me. (Woody Guthrie)