Webtrends Analytics 9 Adminstration Guide, November 2012
As a best practice, you should create a policy that describes how your organization uses first-party cookies and the differences between anonymous opt-out and full opt-out.
Make it clear to visitors that accepting the opt-out cookie from your web server is the mechanism from preventing your first-party tracking cookie from being set and prevents data about their activity your on your site from being collected. Cookie-wary visitors should be aware that if they delete the opt-out cookie, your web server identifies them as a new visitor and sets a first-party cookie that can be used to collect data.
You can view the opt-out language that Webtrends Inc. uses at the following URL: