This is to my mind a profound quote/statement. It rings many bells as to why these two senses dominate the martial arts. I believe wholeheartedly that this goes farther back than modern communications. The first moment of communications be they the grunts and gestures of ancient humans to today's ability to communicate in one form or another where eyes and ears dominate.
Consider teaching or instructing practitioners of martial arts. If a practitioner has a dominant sensory mode of seeing they can have an advantage over hearing and without exception touch. Since martial arts like karate involve moving the body the sense of touch, with restrictions, can aid a person who is identified as touch dominant to learn quickly. I can extrapolate from this that Sensei who have not identified this aspect of teaching can find their participants being less that could be. Imagine you know this tidbit of information and use it to ensure that all your practitioners get the most out of your guidance, knowledge and experience.
In most the left brain processes information that comes in patterned chunks of information one after the other. This is like numbering and the letters of the alphabet. The left side attends to those parts and pieces while the right side "wholes" not formed in logical patterns. The left is mostly in favor of the eye and ear senses while the right side touch. The other senses beyond sight, sound and touch are nonexistent for this lesson, i.e. taste, etc.
I quote, "The effect of our concentration on training the left brain and letting the right founder about without help means that we educate and foster a dominant sense mode of eye and ear, neglecting the other touch dominant sense mode. If you have a practitioner who suddenly becomes frustrated with your efforts you might try to discover if their sense mode is touch vs. the dominant seeing and hearing.
When discovering methods to pass along all that knowledge, skill and enthusiasm for your system remember that although the eye and ear dominant in communications, i.e. teaching, you may discover that touch can benefit your efforts. In the greatest of all scenario's a Sensei who can incorporate seeing, hearing and touching to train and practice may benefit the participants greatly and thus the dojo. The skill then can be to determine the dominant sense and emphasize instruction individually to achieve greater results - skill, knowledge, and proficiency.
Once again give attention, thought and discovery to the meaning of, "The eyes must see all sides. The ears must listen in all directions."
Elgin, Suzette Haden, Ph.D. "More on the Gentle Art of Verbal Self-Defense." Prentice Hall. New Jersey. 1983.