most, if not all, of Buk's prose and poems have been more or less "edited"
The poetry published while he was alive is almost all intact.
Any changes I've found so far (during close comparison of about 500 poems) have been minor. Some look like transcription mistakes rather than editing. I still have more than 1000 manuscripts left to compare, so I'll let you know how that pans out when I'm finished. In about 15 years.
But just in the past few months I've compared about 300 manuscripts to the published versions, covering 1975 to 1980, and of those manuscripts maybe a dozen that were published while Bukowski was alive looked like they were intentionally changed. And those changes do not
include the kinds of things we see in the posthumous changes: that is, removal of references to drinking, drugs and other unsavory activities. They just look like sloppy editing.
It certainly doesn't seem like that was the case for the prose though. But it remains to be seen if anything was left unmolested there. It doesn't look like it based on what David is saying, but I don't know how many he's compared (and no one will believe you until you have a mountain of examples, and even then most of them won't believe you).
And not to be contentious, but comparing the published weeklies to the book versions isn't really the same as comparing manuscripts to published versions. We know the manuscripts we Bukowski's intent
at the time he typed them (and yes he did revise and re-use poems often - but in revising them he didn't change the intent
of the poems). You can't really say the same for the weeklies, because there's an added variable in those with the publishers, transcriptionists, etc. Another layer between what Bukowski wrote and what Martin published.