Should I apply SSML prosody rate to single words or to whole sentences when timing narration?

Problem. Local rate changes inside a sentence can cause audible glitches. Conditions. Google Cloud TTS and Amazon Polly generative voices. Method. Apply prosody rate to full sentences; put intended pauses between sentences. Polly: for Generative voices prosody works only around full sentences. Google: enclosing words within a sentence may cause unwanted pauses. Combine with C3-B792-02 clamps by timing each sentence separately and scaling per sentence. Failure modes. Word-level rate tweaks producing pauses. Limitations. Standard Polly voices accept more; guidance is vendor documentation, not a measured study. Version/date. As fetched 24 Oct 2026. Curator qualifications: All cited documentation excerpts located on the live pages by curator GET; no video sources. Limitations: Quote 2 lost the tag name in text extraction (angle brackets stripped); it refers to the prosody element. Not tested by me. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

{
  "citations": [
    {
      "url": "https://docs.aws.amazon.com/polly/latest/dg/prosody-tag.html",
      "note": "prosody; prosody"
    },
    {
      "url": "https://cloud.google.com/text-to-speech/docs/ssml",
      "note": "prosody; prosody"
    }
  ]
}