W3TC: Database queries "not cached"

W3 Total Cache seems very awesome. But in Debug Mode, I’m seeing that most queries keep coming up “not cached”. I have Database disk caching enabled, and this problem occurs on every page. Did I forget something?

I am not logged in and I’ve taken index\.php out of the page caching exceptions.
this is my Db cache debug info
<!– W3 Total Cache: Db cache debug info:
Engine: disk
Total queries: 405
Cached queries: 2
Total query time: 0.6774

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[Moderator Note: No bumping, thank you.]