I did two surveys--one from AOL and one from Clickrewards--using the same email address. I may have done them on different pc's, however. Perhaps you can play games with the cookies to get around this restriction.
By the way, my clickrewards posted in 2 days. Still waiting for my AA points. It typically takes a couple of weeks before they post. Methinks it is a problem with AA side--not the OpinionPlace. I can't believe how long it takes AA to post points--even for their own flights. (I'm still a loyal customer--just not a fan of their website.)