"An extrinsic norm crucial to comics is the interpretation of a figure reappearing in several panels as one and the same figure shown at different moments in time (usually in chronological order)… Usually it is assumed that the event represented in the second panel happens after the event represented in the first one…"
This constraint is no doubt what led Saraceni to posit a principle of sequential images that weighs "new" versus "given" information across a sequence. It's also a type of constraint placed by Gestalt organization: Continuity.
However, what struck me on this reading of that quote, is that this schema is exactly the sort of thing that people who lack knowledge of the visual grammar (or who have a competing grammar) have trouble with.
For instance, kids below four years old seem to have no ability to make coherent sense of connecting juxtaposed panels — they can recognize the meaningful content of the things in each panel, but they can't seem to connect them as part of a narrative sequence. (They also seem unable to recognize any representations in the images that are predicated on understanding the causation between panels).
A comparable thing happens with the native Australians who use sand narratives. They draw their narratives unfolding in the same space over time, and when presented with juxtaposed panels, think that each panel is a new scene. For them, their own system inhibits this recognition of continuity across panels.
What's also striking is that there are tons of examples where this constraint is not upheld immediately — many (most?) sequences don't feature the same characters over and over in panels. This is one of the reasons that a linear approach to sequential images (like "panel transitions") just can't work.
For example, let's say panel 1 shows person A, then panels 2 through 4 show other things, then you're back to person A at panel 5. You can't just integrate 4 and 5, because you would have had to lose track of person A through 3 panels. Rather, you have to keep them and their actions in mind somehow. Transitions can't capture this relationship.
There has to be a way of upholding this constraint of continuity across longer distances — which thus requires a bigger system than linear sequence alone provides.