On History: Assembly Line Origins?
(The art accompanying this post is the original rough layout for the page in which Eisner explains his approach in The Dreamer. All of his page layouts for that book can be seen here.)
What I'm wondering, though, is how/where did Eisner hit upon the idea originally? I've seen/heard it referenced almost every time the Eisner-Iger shop is mentioned, but there's very little in the way of details. In fact, The Dreamer is about the most elaborate version I've found, and he literally spends only one panel on it. From Eisner's own accounts, he didn't seem too business savvy at the time, so it strikes me as odd that he might lift the idea wholesale from Henry Ford. Also, I doubt he would've woken up one day and suddenly hired fifteen people to help out; he would've picked up one guy here, another there over the course of weeks and months, so even if he did have a flash of inspiration, he wouldn't have had the resources to implement a full assembly line at the outset anyway.
So some kind of gradual approach seems to make the most sense. Maybe start with "I'll write the story and do some rough layouts, you finish it and make sure everything looks polished"? Then perhaps "I'll write the story and do some roughs, you write in the dialogue and draw the figures, and you fill out the backgrounds"? Then "I'll write the story, you do some roughs, you write draw the main figures, you drop in the dialogue, and you finish it"? Something kind of like that makes sense, right?
But how much experimenting did he do with that? How long before he settled on a single methodology? What were some of the options he might have tried that didn't work out well?
And one thing I've always been struck by is that Eisner has mentioned on more than a few occasions that different artists worked on the main figures than the backgrounds. I understand that's not an uncommon practice in manga, but I can't recall when I may have last heard of that approach being used in US comics. Maybe from the waning days of the newspaper adventure strip? Was Milton Caniff the last major comic artist to employ this approach? (It should go without saying that the foreground/background division of duties is still standard in animation.) When/where did that comics assembly line process shift into the penciller/inker model we're more familiar with? Is it indeed more efficient than a foreground/background approach?
I find it a little curious that, for as much as has been written by and about Eisner, and for as significant as that division of labor was/has been to comics, that there seem to be scant details about how it actually came about. At least, as far as I can find.