Free!
None of that counting syllables or beating out rhythms against your desk. Nope. See, Lucille Clifton's language is straight shooting. She's going to express exactly what her speaker thinks and feels – which means that fancy metrical patterns would only obscure the immediacy of her message. It sort of makes sense – after all, Clifton's speaker is really confronting all of the social codes which dictate how a woman "should" look in order to be beautiful. Stepping outside formal codes allows her confrontation of social codes to have even more impact.
Working without strict adherence to some kind of form or meter doesn't mean that just anything goes, though. Clifton's language is stripped-down, without any excess adjectives or turns of phrase to gum up the images that she presents. What we get is a collection of assertions without elaborate description. We don't believe that our speaker has amazing hips because she compares them to Amazonian mountains (in iambic pentameter, of course). Nope. We believe that she has amazing hips because she tells us so directly. End of story.