Using In A JavaScript Literal
This is not how the XML parser sees things. It reads sequentially.
First is sees an open script, then it sees the CDATA which simply says escaping is not necessary. It then sees the close script tag, which by what appears to be coincidence is not needed to be escaped, and it closes the script block there, since one is open.
more on wwco.com
Detailed explanation of one of the JavaScript caveats.