If you choose to hide the pollresults, guests are not able to open the thread/topic at all. If a guest try to read7open the topic, he gets an empty screen with this message "FYI, Sorry, we have no one registered with that name. Use your browser's back button to try again."
I think it would be better to let the guest see the topic and the polloptions, and provide him with a message and an option to log in, but not let anyone see the pollresults.
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