LaTeX-Skim Sync

I recently started using John Wiegley’s use-package for my Emacs init files. For Auctex, I used

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(use-package tex
    :ensure auctex)
and everything worked except for sync with Skim on OS X. C-c v would not launch the Skim, even though I was confident that the Skim was set to be the default viewer. Instead, no viewer would launch, and I’d see “View command: dvi2tty -q -w 132” in the minibuffer.

After seeing that some others had used a slightly different configuration, I changed mine to

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(use-package tex-site
    :ensure auctex)

and everything started working fine. I still have no idea why, but it may help someone else.