SIBILANTS. the close proximity of sibilants is death, because it's hard to pronounce them clearly without sounding unnatural and awkward. e.g. "Grace shed her clothes, smiling shyly:" I try to articulate words as clearly as possible, to compensate for a tendency to mumble (and wow, I didn't realize how unarticulated my speech was until I started podficcing), and when sibilants are right next to each other, they tend to mash up and run into one another unless I come to a full stop between each word, which sounds weird.