All forms of content are valid. On one of my sites I write REALLY LONG content (many of the "pages" running between 87,000 to 116,000 words) as a single document. Offered as fluid HTML and PDF. Those interested in that content would be mighty p]ssed if offered in 500 word chunks which forced them to load a web stripper to get it then assemble it (you do know that's what some do with what thrills them). That LENGTHY content is the hardest hit by all my visitors, though they do read the shorter works as well.
It's all a krap shoot. What the leeches seek they will find, and if you offer it, and it is well written, they will tell others---and at the end of the day that's what we desire.
Just speaking from the other side, eschewing the shorter and shorter sound byte pages which irritate me personally and, I suspect, a significant portion of the web.
Ultimately, it all comes down to diarrhea of the keyboard. Can you continue to spew? Can you maintain the pace? Can you have fun doing it? Last time I looked the carpenter who kept hitting their thumb with a hammer wasn't having very much fun and switched jobs to become a politician. :)
added: If you are writing for SEO you are not an author. You are a mechanic. See my "passion" post above. Nothing wrong with that, but if writing for SEO you are a copy writer, an ad man, a snake oil salesman (and all of those are COMPLIMENTS for that trade). Just don't pee on my leg and tell me it's raining.