Not only he covers the technical structure of a comic, but also its psychological aspect: its appeal and the reason he said "deliberate sequence". Because the story is an experience if the reader can put themselves into the character's shoes.
However, I think it really is a matter of taste when it comes to art style. He states that the more realistic the style is, the further away we are from immersion, and instead we become bystanders just like a cinematic experience. In my experience, I see myself in more elaborated scenery, such as in Takehiko Inoue's Vagabond than in, say, Garfield.
McCloud also emphasizes the difference in space and time depending on the text that accompanies each panel. In a wordless panel, the viewer can take in the details of the environment, the action and position of characters, as well as what they mean together. In some cases, wordless panels can be fast-paced because we take less time taking in details than reading text. It becomes a simultaneous experience. On the other hand, words slow time and divide the panel into different actions.
This is especially true in Hogarth's illustrations, where the details take time to consider, but we think of the scene as a simultaneous experience. You can see it in many ways from different angles and not know who started an action before the other. All characters are in the same level in actions, so the composition must be taken into account to understand the story. It's not explicitly linear, but there is a story that is understood in the historical context.
Maybe the first sequential art with morality.
If there were dialogue in his illustrations, then the meaning of the illustrations will change completely because then we would be forced into a linear understanding.
In short, the layout of comics is an important part in slowing or hastening the pace of the story. More panels drag because attention is focused on words and their meaning, while less panels shorten understanding time because they accommodate larger images with much more detail.
Cartoonist Track:
What Understanding Comics also explains is that the pace of the story can be manipulated via "shots". Depending on the shots, the reader can tell where they are supposed to be, who they are meant to pay attention to, what mood we're to feel. Each panel should have a considered shot, a plan of composition, position and pose of the character, to guide the eye of the reader. I wanted there to be a peaceful mood, so I centered the character with minimal dramatic gesture, and gave less details in the background. A centered composition gives a sense of balance, while the lack of detail in the background gave the reader time to take in the meaningful details (such as pose and lines the characters).
The first panel is the establishing shot, and in order to give the reader some understanding, I gave the scene details. This helps the reader fill in the gaps in subsequent panels, because the reader already knows where the characters are supposed to be at.
McCloud also places importance in lighting, but I believe that depends on the graphic novel you're meaning to make. There are styles that do not require shading or values.
Lastly, the 4th panel is in a dutch angle, not because it's an action or unbalanced story beat, but because I wanted the short-haired girl to keep us grounded (vertical position). After all, we are looking from the short-haired girl's POV.
