You do know what an 'affirmative duty' is, don't you? Specialized are only required to meet the obligations of the affirmative duty if they wish to uphold the trademark. There is no requirement or obligation, as you suggest, "to pursue all infringement of their trademark". They only have to take the action if they wish to enforce the trademark.
They do not, as you suggest, "...HAVE to sue any company who infringes upon it, whether they're a big guy, or a little guy, or whether it's threatening to them or not...". They can decide not to but what they than can't do is subsequently seek to enforce the trademark if they have not undertaken any affirmative action in relation to the relevant breach.
And I would point out that the US and Canada have different legal systems and different trademark systems. It's a bit silly to quote US legal blogs in relation to Canadian trademarks. Why not simply go to the
Canadian Intellectual Property Office where all the information is available?
Anyone who has studied international law (which was part of my degree at university) will be familiar with the WIPO, the Madrid Agreement and the Madrid Protocol.