Sounds like she sees the alternating long and short lines of Sea Change as a "new music," a mix of Whitman and Williams (from an interview with Diedre Wengen):
Graham: Well, the alternation of the very long and very short lines, spread over cascading sentences, with a sense that the music moves out for a long moment, then drops, then recovers and "hovers" again, then drops again (accelerating) is a new music for me, and, just from a technical point of view, one of the reasons I found my way to the book. "A new music is a new mind" says William Carlos Williams—and this was a sudden new music which took me to new places in my emotions and thoughts. And Williams, the second great poet of our "democratic" experiment, the formulator of the notion that there are "no ideas but in things", is definitely behind the short lines. But our first great poet of the American Democratic experiment is the visionary master of the overly-long line, Walt Whitman, who says, "do I contradict myself? Very well then, I contradict myself. I contain multitudes." So, letting the sentences move along this grid of very long and very short lines—feeling both of those prior "socially aware" poets in my ear—I also was able to enact a sense of a "tipping point"-the feeling of falling forward, or "down" in the hyper-short lines at the same time as one feels suspended, as long as possible, in the "here and now" of the long line—so that the pull of the "future" is constrained by the desire to stay in the "now," which is itself broken again, as a spell is, by the presence of the oncoming future. This also involves a tipping back and forth between hope and the brink of its opposite.