> but I have moved into self-publishing.
As near as I can tell, publishers have one and only one purpose in the modern world: Publicity. They might as well change the name of the biz to reflect this, because it is the only differentiator they have.
They also provide a bit of financing, sort of like how movie studios are basically banks who specialize in investing in one particular area. But with the typical tech book advance coming in under five figures, this isn't very big.
Fair enough, and I'd go further to say: Several of us have access to higher-quality editors and (certainly) tech folks for review than most of the publishers I've dealt with.
My chapter walked through designing and implementing a custom binary protocol running over UDP for realtime network communication over a LAN. One reviewer suggested that I expand on a bit that went something like, "Create a new project in Xcode" with a step-by-step along the lines of, "1. Open Xcode and pull down the File menu...." This seemed to be well below the level I was aiming for, but of course I could never get anyone at Apress to tell me who they agreed with.
The copy editor was decent but not technically minded, so I had to explain a fair amount. I imagine that technically-minded copy editors are hard to come by, but still, this is a technical press.... The copy editing process was atrocious. I had to download some crazy Adobe software to review the suggested changes, and for some reason they do the indexing before these final changes, so I had to ensure that any alterations didn't reflow pages too much.
When I self published, I ended up crowdsourcing people for these functions by recruiting on my blog and on Twitter. I got a couple of dozen fairly competent people and we were able to divide up the book so that nobody had to do more than a couple of chapters. (Some ended up doing much more, but simply because they wanted to.) That ended up working pretty well, although obviously not every prospective author will have the ability to recruit a couple of dozen helpers like that.