Why Does The TPP Repeatedly Require Stronger Copyright, But When It Comes To Public Rights... Makes It Voluntary?

We've already written a few stories about the newly leaked IP chapter of the Trans Pacific Partnership (TPP) agreement, and how the US is pushing back against any attempt to punish abusers or to support the public domain. But in going through the documents, another key fact strikes me. Throughout the document it's designed to absolutely require strict copyright laws and enforcement. But when it gets to the public's rights, the so-called "limitations and exceptions," the agreement tosses up a big fat "meh, that one's voluntary." We've already pointed out how ridiculous it is to refer to things like fair use as a "limitation and exception" to copyright, when it should be the public's rights -- and copyright restrictions are, by their very nature, a limitation and exception on those natural rights. But it's even worse in the TPP. As you may recall, the USTR announced, with great fanfare back in 2012, that "for the first time" it was moving to include such "limitations and exceptions" in the TPP. The USTR thought that this would appease people who had been complaining about the entirely one-sided pro-copyright extremist position that it had been pushing for decades. Of course, when the details came out it showed that the USTR was really proposing a limit on fair use by proposing a rule that would act as a ceiling for the kind of fair use-like protections for the public that would be allowed. Now, with the latest leak, there's something else that's noteworthy. Here's the text of the "limitations and exceptions" clause in the copyright section:

Article.GG.Y {Limitations and Exceptions} Each Party shall endeavour to achieve an appropriate balance in its copyright and related rights system, inter alia by means of limitations or exceptions that are consistent with Article QQ.G.16.1, including those for the digital environment, giving due consideration to legitimate purposes such as, but not limited to: criticism; comment; news reporting; teaching, scholarship, research, and other similar purposes; and facilitating access to published works for persons who are blind, visually impaired, or otherwise print disabled.

Notice the text I bolded: "shall endeavour." In other words, "well, you can try for it, but you don't need to do it." Now, look at basically all of the other text and it's straight up "shall." No "shall endeavour" for everything else. Everything else is required. Only the stuff about the public's rights lets countries not do it so long as they claim they tried. Here, just for comparison's sake, are just a few of the other "shall's":

Article QQ.G.1: {Copyright and Related Rights/Right of Reproduction} Each Party shall provide that authors, performers, and producers of phonograms have the right to authorize or prohibit all reproductions of their works, performances, and phonograms in any manner or form, including in electronic form.

And...

each Party shall provide to authors the exclusive right to authorize or prohibit the communication to the public of their works, by wire or wireless means, including the making available to the public of their works in such a way that members of the public may access these works from a place and at a time individually chosen by them.

And...

Each Party shall provide to authors, performers, and producers of phonograms the right to authorize or prohibit the making available of the original and copies of their works, performances, and phonograms through sale or other transfer of ownership.

And...

Each Party shall provide that in cases where authorization is needed from both the author of a work embodied in a phonogram and a performer or producer owning rights in the phonogram, the need for the authorization of the performer or producer is also required.

Etc. etc. By my count, the copyright section includes thirteen "shall provide" and just the on