(GOODNESS I'M SORRY THIS IS SO LONG, It's a bit clumsy but I hope something here provides some tiny amount of insight!! @u@ )
Honestly when I first read about this, my reaction was essentially, "What? no. I'm calling B.S. Comic artists don't really do this." SO YEAH I FEEL YOU, IT, DEFINITELY FEELS LIKE WEIRD MADE UP NONSENSE. But it turned out to be real -- now, I do absolutely think about this in every page!!
I do draw those arrows on my own work, but it tends to be a really early stage thing, at the point where my thumbnails are illegible to anyone but me, and in later sketches it's drawn very lightly, so it's tough to find Actual Examples without just drawing incomprehensible arrows on my own work. But here's kind of how I like... approach it I guess?
A lot of times I do sort of start sketching those lines, just to give me a sense of "this panel should flow into that panel" when I'm just starting out. This is how the readers eye will naturally scan! These aren't like, the FINAL PATH OF THE EYE, because that gets more complicated when I actually start sketching figures in, but
the important part is kinda how they flow into each other -- this isn't so much a thought of "THERE MUST BE AN ART ELEMENT POINTING AT THE NEXT PANEL" -- tho sometimes that's true -- it's more that I want to make sure I'm pointing things in the "right" direction and not leading away from the place I want a reader to look next.
so for example, in this hypothetical setup, I'd face the character so he's looking in the direction we're next going to be looking, because it's natural to follow his eyes. (You can
use stuff like this to INTENTIONALLY disorient readers but in most cases that's something you want to avoid)
I do have a small example of when this came up in my own comic, in the way word balloons were laid out! This is from my patreon but it's a few months old at this point so I guess, consider it a sneak peek of patreon content. xD
I had dialogue laid out like this initially:
this created flow problems in two places -- we would read the reaction before we actually got to the thing that was being reacted to:
I rearranged the problem balloons to get this:
The break in balloons between "i think so" and "you're person shaped" gives us a chance to stop and see her face, and see what she's reacting to. That's not perfect, but it was an improvement so I went with it!
Note also that this version, the "I think so" balloon is more in line with that flow path from panel 2 to panel 3, whereas the last one required our eyes to do more upwards gymnastics to get there which made it a bit more awkward.
For the last panel, I still needed a word balloon in the same spot as the "!!" balloon (to pull your eye over to that side of the panel, so you'd see Xira's nervous face instead of jumping straight down to the screaming), but instead of having that be the reaction to the screaming, it's him starting to say "we're safe!" Changing it to a cut-off statement means the timing follows the order we're reading it in a lot better. You move to his word balloon, "hear" it cut abruptly, and then see him reacting to a scream -- approximately what would actually happen if you were in the room watching this.
So that's kind of how the idea of "flow" affects my thought process? A lot of it is very loose for me, not so much in the sense of "art elements must create literal path from panel to panel" but more like, the motion of figures and the direction that characters are looking should play into the path our eyes are travelling, so that we kind of follow-through that motion into the next panel -- and word balloons play a HUGE role in this since we're trained to look for the next balloon; this plays into making sure we read the balloons in the right order, that we don't accidentally run into a balloon early (which might not confuse us if we can tell it's not the "next" one, but does feel awkward and break immersion) and can sometimes be used to move the eye around the page by counting on the reader to jump to the next balloon.
Does this hit on any of the things you were wondering about? If I'm kind of missing the actual question or you have questions about anything that I described strangely, by all means feel free to ask or clarify and I'll be happy to see if I can put my thoughts into words more clearly!! ;u;