I do have a comment on this one:
> “Users don’t read”
> An overly used argument to convince clients and stakeholders to cut copy length in half. If you made this far to this article, you’re living proof that this statement is untrue.
The real principle here is that users don't read anything that doesn't look like it will help them do what they're trying to do.
In the case of the article: Sure, I read the article, because I wanted to read the article. But notice I didn't read the titlebar, the subtitle, the author, the nav, the footer, the newsletter subscription form...
Someone reading copy probably wants to know something about your product. Depending on what they want to know, they might skim around the page looking for the most relevant thing – for instance, looking for a header named "Specs" when trying to find battery life.
Making your copy shorter will certainly make that task easier and save their time, and it'll probably make it less likely that they'll decide they didn't want to know things about your product that much.