There is a lot of handwaving going on here. The below, however, is an egregious misunderstanding of how percentages work. That, or it betrays very sloppy work. Doing it right would actually make the specific case they make stronger.
"There are also potential opportunities to leverage the fact that the speed of light in a vacuum is 35% faster than in a typical glass fiber."
This is just wrong. The speed of light in a fiber is ~2/3 slower than in a vacuum. That means that the speed of light in a vacuum is 50% faster than in a fiber, not 35% (~1/3) faster!
"There are also potential opportunities to leverage the fact that the speed of light in a vacuum is 35% faster than in a typical glass fiber."
This is just wrong. The speed of light in a fiber is ~2/3 slower than in a vacuum. That means that the speed of light in a vacuum is 50% faster than in a fiber, not 35% (~1/3) faster!