This may get you some dirty looks, but can you challenge the people who want the docs to tell you what they use them for, what they need to do their jobs? It's a long and sad road to guess, get lots of complaints, guess again, get lots of complaints, etc. The best news is when you find somebody who'd be happier to have you come by and spend an hour talking at the white board and skip writing the
doc altogether. He learns more and so do you!
I've given up on docs but I write tons of documentation in a web site (Wiki). A reader can follow a function through the architecture from end to end, browse many functions in the same level of abstraction, follow links up for an overview or down for details. A
Word doc with a hierarchical table of contents is too hard for me any more.