it's a bithidden in the advice to writers and, most especially, the cranky interviews at the end of the book, though

Ah, perfect - I actually have this one but haven’t ever figured out the best way to get started or pick through it

For your purposes, I'd probably read the Introduction and then skip to the interviews. Then skim through the other chapters as you have time/inclination.

Here goes nothing!

I can't guarantee that it'll be fruitful, but it's Delany so it will be entertaining and not lacking in strong opinions