Blog writing is different than book writing because you need to assume your blog's readers are distracted.
Many readers will skim through an online editorial when it's written in standard 4 sentence paragraph format. Readers who skim are more likely to jump to the next paragraph long before they finish reading the current one.
Skimming is a natural part of online life. We don't have enough time to sit and read every word, so we jump from paragraph to paragraph trying to glean the most important bits.
To combat skimming, and to make sure your readers do read the most, you need to break your blogging format from 4 sentences per paragraph to 2 or 3 sentences.
Another difference between book writing and blog writing I learned through many frustrations when I first began blogging.
One of the biggest mistakes I made during my first 100 Nuggets was assuming everyone would read the entire Nugget from beginning to end without stopping. After all, they were only 400 words long, so why WOULDN'T someone read from beginning to end without interruption?
What I learned was that no one reads a blog post or an email without interruption. It's not like a book where someone will quietly sit with undivided attention. The digital world is wrought with distractions and shiny objects to chase after. We refer to this as the "ferret syndrome" or "ooo-shiny effect."
Not even my original editor gave me full attention. In the beginning she would call me all the time because the Nuggets were too confusing. Sometimes she would ask me what I was referring to when I had already explained it 6 sentences prior in the same Nugget.
Inevitably I would angrily ask "Did you read that from beginning to end all at once?" What I failed to recognize was that, if my own editor couldn't read the Nugget undistracted, then no one else could either.
I'm sure that created a huge learning barrier for my early readers.
Then one day while watching the History Channel the solution dawned on me. Have you ever watched a documentary on the History, Science, Animal Planet, or some other educational channel? Every time the show returns from commercial they give a quick recap so viewers just tuning in can follow the story even if they already missed 30 minutes.
You need to use this "History Channel Method" while writing your blogs. From beginning to end, sometimes you need to repeat yourself and provide exposition of ground already covered.
My preferred method of repeating myself is to use fewer pronouns and more nouns. For example, you might talk about a nice pair of gold earrings in your first paragraph, and you might want to refer to those earrings as "them" or "it" in the next paragraph. But using the "History Channel Method" would mean you would say "those gold earrings will match nicely" instead of "they will match nicely."
Each of your blog post paragraphs should make sense when taken out of context or if someone is interrupted. They each should convey a single, understandable concept on their own.
Sometimes I find that I struggle between 2 sentence paragraph vs. single concepts and pronouns. In those cases I am forced to find fewer, better words to say the same thing, and to have a 5 sentence paragraph.
When it comes down to it, I'd rather have a larger block of words in a blog post than run the risk of confusing readers who get interrupted. Those who really care will read the full, larger block of words.