Apparently the screwballs at TI think that incomplete data sheets are acceptable to customers. The TCA1116 is an I2C I/O expander. The data sheet on the TI web site and everywhere else I could find it contains a cover sheet and packaging information. The absence of programming details is terrible. There's an invitation to get the "full data sheet" by emailing for it but the email bounces.
Wanting engineers to keep using their stuff should create _some_ pressure. Of course, the bean-counters have to be smart enough to understand that a bean saved today may be a bushel basket full that never gets harvested tomorrow -- but, they're bean-counters, so how can you know?
A "design in" tends never to be a "design out". When everyone is doing the same thing (wrt quality, support, etc.) what incentive do they have to add to their costs?
While you may be working on *a* design with device X, chances are, others in your organization are working on designs using components from the same vendor. There's a lot of inertia to fight -- and reps can sew FUD with upper management, your peers, etc. Change upsets the power balance in relationships. Even if you want it, you will inevitably instill fear in others (that they will never EXPRESS as "fear" but their behavior will clearly indicate that this is what is happening)
When the MPU industry started, there was a LOT of diversity. Not just N different variants of ARM, M variants of "x86", etc. And, lots of support (documentation, etc.).
But, that didn't pan out for the vast majority of MPU vendors. Their products just disappeared. They weren't "improved" or "enhanced"... they just went away. Designs gravitated towards specific processors and specific vendors. "Motogorilla shops", "Intel shops", etc.
And, with tools costing many kilobucks, you didn't change processor vendors lightly. "Multiple second sources" (a prerequisite for many of us, early on) gave way to tweaked versions of "familiar products". Not enough of a change to cause all of your personnel resources to lose their value (hey, it's still an 8051!) but enough to ensure you would only be buying your silicon from that ONE vendor. Are *any* products truly second-sourced any more? (drop in replacements)
When the Motogorilla rep at a moto shop got wind that I was talking to TI, NatSemi, Intel and even DEC about processor choices for our next generation product, he was stunned: "You mean I have to COMPETE to KEEP this account??"
Couple this with shortened development cycles and product lifetimes and who has the time/inclination/risk to head down a different path?
The tool that they use to create the PDF should automatically create a ToC -- of however much detail *they* desire (Chapter, Heading, Subheading, subsubheading...) by extracting tags from the text that is being processed. Ditto with the thumbnails.
[Likewise, insert hyperlinks to those "paragraphs" throughout the text (so, clicking on "See section 3.2" in the text brings you *to* section 3.2)]
Enabling/disabling these *displays* is something that the browser/reader should provide.
Thumbnails only have merit in documents that have a variety of different types of content that can be easily recognized "greeked". E.g., "Ah, this is where that big table is located" or "Here are the timing diagrams"...
I've found it very effective to provide "pictoral" ToC's (sort of like a graphic "list of figures") in documents describing user interfaces: "Yup! The screen I am looking for sort of looks like that!..."
When you create the document, you indicate its initial "view". I create thumbnails, etc. but only turn them on in the initial view if I think that they will aid the reader in locating something -- or, gauging the extent of the document (for first time readers)