When I click help in the help menu, the PDF opens right away, but then Premiere freezes for about 40 seconds. I suspect it is trying to download some Internet content, but this behavior needs to be fixed. My Mac Pro is connected to an AirPort Extreme via wifi, but this network is not connected to the Internet, it's just for internal file transfers. If I turn off the computer's wifi, this problem does not happen. I get the same symptoms with Premiere, After Effects, an Media Encoder. All of the help PDFs are downloaded already and show current in Adobe Help.
Thanks for reporting. I'll look into this for you.
Just confirming that you're running Premiere Pro CS6?