I'm reading Bertrand Russell's History of Western Philosophy, which, aside from some obvious biases, is quite enjoyable. In it, he talks about some ancient Greek philosophers. He mentions some who purportedly wrote a ton of books, with one penning some 75 texts. However, no copies of these have survived.
I'm wondering if this number can be at all considered accurate, and, if so, what the editing process would have looked like back then and how long these books would be.
Obviously it's quite hard to parse the exact process of editing of a text just from the extant text itself. One instance where we are fortunate enough to have some help is with Greek scholion. They are sort of commentaries/questions about what the text means, mostly on the Iliad and Odyssey. In and of themselves they're hugely useful because they tell us what the Greeks thought about the Homeric poems. It seems as if the 48 books of what we today call the Iliad and the Odyssey were mostly, but not completely set in stone during classical antiquity, there was variation of words and phrases here and there. Also, because the dialect that Homer writes in is so artificial and weird, and has so many hapax legomenoi that even Greeks were occasionally confused as to what the text meant. Thus they would scribble notes in the margins of scrolls and much of our own Homeric research rests on the efforts of Greek scholars. The upshot seems to have been that slowly a process of consolidation occurred and some inconsistencies were edited out, resulting in a "standard" version being compiled in Alexandria between 200 B.C and 200 A.D. One example of this process that springs to mind from book 24, and forgive me any inaccuracy, I'm quoting from memory, goes "ἐπεί με πρῶτον ἔασας//αὐτόν τε ζώειν καὶ ὁρᾶν φάος ἠελίοιο" (that you allowed me to live and see the light of the sun). The last part "καὶ ὁρᾶν φάος ἠελίοιο" seems to have been inserted later on by these Alexandrine compilers, otherwise the line would be incomplete. Now Homer occasionally does this, leaving a line deliberately incomplete for emphasis, and it is theorised that he did just that there, but a compiler thought it was a bit odd and inserted a couple of dactyls to make the line complete.
This begs the obvious question, why were some inconsistencies and problem lines edited out but others weren't. I don't think that we are ever going to have a satisfactory answer to the question except to guess that these scholars had a truly deep knowledge of the text that they were working with and wanted to preserve the distinctive voice of the original poet while creating a standardised, mostly problem free, edition. Hope this helps, I haven't studied Homer in a few years so I may be slightly rusty. If there's anything wrong please feel free to point it out.