Petitioners assert that “consumables can be thought of as the 3D printer equivalent of ink or toner in 2D printers,”20 but the analogy is inapt. The output of a 3D printer is a three-dimensional physical part, generally built entirely from the consumable printing material. [Lots of words completely irrelevant to the first sentence deleted. -Ed.] In contrast, the consumable toner in a 2D printer is bonded to a flat substrate, and therefore has no structural or mechanical properties’ requirements.
The problem here is that Stratashit is alleging that because there are differences between filament and ink cartridges, that that means that the similarities are invalid and simply don't exist. The fact that both devices use consumables that go into the finished product and have to be replenished when expended,
is, indeed, an irrefutable fact. Attempting to weasel around that
irrefutable fact by ignoring it and instead supplying lots of words that do nothing to refute it seems awfully disingenuous and manipulative to me.
Some non-system manufacturers attempt to mimic proprietary formulations to sell knock-off versions of genuine materials for use with closed systems. Petitioners provide one example, that of third-party non-genuine materials for 3D Systems’ “Cube” line of printers.23 As discussed below, such materials can be ill-suited for the uses Petitioners seek to facilitate through this rulemaking."
"Can" be? They are trying to imply the Copyright Office shouldn't allow people to try non-price-gouged filament because it "can be ill-suited." The printers' owners are not to be able to find this out for themselves, you know, "just in case." Because it's the Copyright Office's job to play nanny and make sure you don't use a filament that "might" not work, even though the
overwhelming probability is that
it will work just god damned fine, thank you very much, you lying liars who lie.
BTW, here is a photo of a box that was printed with Stratasys filament, and then with Octave filament
using a hardware hack. How?

Is this?

An act of copyright infringement?
Then, there is Part II, which is a laugh and a half!
II. PETITIONERS HAVE FAILED TO MAKE A PRIMA FACIE CASE IN SUPPORT OF
THEIR PROPOSED EXEMPTION.
To make a prima facie case for an exemption, proponents bear the burden of proving that (1) uses affected by the prohibition on circumvention are or are likely to be noninfringing, and (2) as a result of a technological measure controlling access to a copyrighted work, the prohibition is causing, or in the next three years is likely to cause, an adverse impact on those uses.48 As detailed below, Petitioners have failed to make either showing.
OK... this is the standard they are setting themselves up to meet.
Petitioners Have Not Demonstrated Any Noninfringing Uses Enabled by the Proposed Exemption on Circumvention.
i. Petitioners Cannot Meet Their Burden Without Describing the Circumvention Activities for Which They Seek an Exemption. “The burden is on proponents to show that circumvention of TPM is noninfringing....”49 An exemption will not issue if proponents do not provide sufficient information about the circumvention they seek to facilitate through the rulemaking process. 50 Without such information, the Register and the Librarian cannot evaluate
whether the act of circumvention creates an infringing copy or derivative work, or whether it falls outside of the scope of the rulemaking because the technological measure circumvented does not control access to a copyright protected work.51 The Register has emphasized that a class cannot be designated “in a factual vacuum.”52
Public Knowledge/LCA's comments can be found
here. I am not sure why they want to avoid delineating any of the methods for circumvention, although I suppose it might be to avoid giving Stratasys any information that the company could use to stop people from using those circumventions.
Of course, information on how to circumvent a 3DS printer's Customer Experience Improvement Extortion Module is freely available online.
Here is an example of a mod that does nothing to the software on a Cube printer, but fools it into letting you use 3rd-party filament.
This mod works with a Stratasys Dimension SST 768 printer, and works by removing log files from the hard drive and re-flashing the filament spool's EEPROM.
If all you're doing is downloading the EEPROM off the spool, never giving anyone a copy of it, reflashing it over and over, and zapping some log files, is that infringement?

Is that the same thing as running a dissassembler on their software and handing the source code out to anyone who wants it? Are you giving even one line of their source code to someone who doesn't have that printer?
...No? Okay, glad we're on the same page.
Is the fact that PK/LCA's comment doesn't contain information anyone can look up on Google grounds for dismissing their request? Perhaps, on some minor procedural issue. This is an important matter and it needs to be discussed, so letting it slide on some minor technicality would be ill-advised, I think. The "Librarian" referred to in these docs could just look these things up him or herself, yes? Should "You didn't hand over information that would take anyone literally five seconds to find on Google" be adequate reason to dismiss a matter of such gravity? I say that would be a travesty.
Here is an interesting quote from
an appellate court ruling from 2003 regarding circumvention of trivial nonsense designed to coerce consumers:
Chamberlain's proposed construction would allow any manufacturer of any product to add a single copyrighted sentence or software fragment to its product, wrap the copyrighted material in a trivial "encryption" scheme, and thereby gain the right to restrict consumers' rights to use its products in conjunction with competing products.
The court told Chamberlain

that it couldn't

game

the system.
Oh, hey! That means that a
legal precedent in good standing exists, which indicates the Courts' preference not to play bully for manufacturers who want to lock their customers in.
Circumvention to Use Non-Manufacturer Approved Materials Does Not Enable Noninfringing Uses.
To the extent that Petitioners’ proposed uses can be evaluated, the proposed uses do not qualify as noninfringing uses within the meaning of Section 1201(a)(1)(A).54 As the Register stated during the last triennial rulemaking, “[a]n exemption may not be based simply on perceived beneficial or desirable uses,”55 but must be one of the uses expressly protected by Title 17, such as fair use as described in Section 107, certain educational uses described in Section 11, and certain reverse engineering described in Section 117.56 Circumvention of a technological measure that does not control access to a copyright-protected work is beyond the scope of the rulemaking and cannot support an exemption.57 Circumvention that creates an unauthorized derivative work or copy is infringing unless it constitutes a use protected by Title 17.58
Time to trot this out again:
This is an example of a non-infringing use. This is Title 17. Section F indicates that the title is not to be used against people who are reverse-engineering something solely for purposes of making one program compatible with another. Why would there be any ethical difference between making two programs compatible, and making a printer compatible with a spool of filament? They are both done for interoperability. That one action concerns software, and another hardware and feedstock, is
utterly irrelevant in any ethical consideration.
Software, hardware, and feedstock DO NOT have ANY innate properties that bear on the question of whether one should be interoperated with more or less freely than another. They imply a distinction without a difference.