Mike....sorry but that is beyond HORRIBLE and no way anyone can learn from a page which will have been broken into several sub-pages destroying the continuity of the equations. Rarely will you ever see a math text where the examples/solutions span other than the facing pages...which also represents a reason why textbooks are going to take a LOOOONG time to move to ereaders...many are engineered/designed to use two facing pages not flipping back and forth. But if given the ability to see at least one full page, I would say maybe some students would adapt OK but even if the formatting of the PDF is retained on a 6" panel device the page had to be split into multiple screens which adds a significant layer and distraction to the student.
But the example you show is just proof a 6" device has no place in a technical course yet. And any excuses offered is simply marketing wonk spin. Something I have no tolerance for what-so-ever.
Or as a potential customer I would counter with, OK, so the Boox 60 is the best of a room full of bad options...so, from that POV it's the best, feel better? I consider that intentional misinformation the leads to unreasonable assumptions on the part of the person shopping for a device for exactly what I have been describing. It shows a totally lack of concern for doing a job ethically rather than just pushing sales through the register.
Sorry, this is something I am pretty adamant about...and also am backed up by what the original Kindle DX trials showed and the universities involved reported...and those were 9." devices. Though I would say a 9.7" device with a Wacom would be light-years ahead of any 6" device as well as the DX (completely useless for most college student needs.
So, if your company is fine with being the best of a room full of bad options, great for you...