"Canonical URL Tag Usage" recommendation in SEOmoz "On-Page Optimization" Tool

[gerardoH]

Here comes another one related to SEOmoz "On-Page Optimization" Tool.

The tool says the following about one of our pages:

---

Canonical URL Tag Usage

Explanation: Although the canonical URL tag is generally thought of as a way to solve duplicate content problems, it can be extremely wise to
use it on every (unique) page of a site to help prevent any query strings, session IDs, scraped versions, licensing deals or future
developments to potentially create a secondary version and pull link juice or other metrics away from the original. We believe
the canonical URL tag is a best practice to help prevent future problems, even if nothing is specifically duplicate/problematic
today.

Recommendation: Add a canonical URL tag referencing this URL to the header of the page.

---

Let's say our page is http://www.example.com/brands/abc-brand and on its header we'll place the following tag:

Is this correct?

I thought the canonical tag was meant for duplicates of the original page, for example:

http://www.example.com/brands/**print**/abc-brand

href="http://www.example.com/brands/abc-brand**?SESSID=123**

Thanks in advance.

[Kotkov]

If you put canonical tag on page "/abc-brand" it will also be on"/abc-brand?sessid=123". That would tell search engines that this is the same page and they would not consider them as duplicates