Please see attached review.




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Document: draft-ohye-canonical-link-relation-04.txt
Reviewer: Brian Carpenter
Review Date: 2011-12-14
IETF LC End Date: 2011-12-29
IESG Telechat date: 2012-01-05

Summary:  Almost ready (LC comments not addressed)
--------

Minor issue:
------------

> 1.  Introduction
>
>   The canonical link relation specifies the preferred URI from a set of
>   URIs that return identical or vastly similar content, ...

I don't understand the phrase "vastly similar". I don't understand what algorithm
tests for vast similarity. 

The same applies to "extremely similar" in section 3 and "similar to" in section 5.
Also, "similar to" is weaker than "vastly similar" or "extremely similar"; so does
section 5 intend to weaken the earlier text? It seems that exactly the same phrase
should be used in each case (not just a vastly similar phrase).

This doesn't matter so much when it's a human designating the canonical relation.
But it can only be a matter of time before code starts to do this (which page is
canonical among a set of generated pages?). A vague word like "similar" turns this
into an AI problem.