[eschwartz]

Why, oh why, are you using a semicolon to separate authors, when calibre uses "&".
Why, oh why, are you using a semicolon to ALSO separate two author first names when they have the same last name?


And calibre is certainly trimming the filenames, since I assume the author (singular) "Frank; Brian Herbert; Kevin J. Ander" is actually "Frank; Brian Herbert; Kevin J. Anderson".
(But it should be "Frank Herbert & Brian Herbert & Kevin J. Anderson".)

Now, I would expect, if the metadata as definitely the same, that calibe would rename the author folder. It is possible that when shortening the path, it keeps old folders (I doubt it), but in any even, if you temporarily rename the author, it will recalculate the values and put them all together.

EDIT: well, chaley seems to be implying that calibre does, indeed, create the entire path independently, and split it arbitrarily.
Can't say I'm too terribly surprised though.