This approach tends to work better for articles that are jam packed with information and/or those that take a broad, aerial view of the topic, but it can also work with articles that are a close up view of one specific topic. For example, I've written many articles on how to create an effective resource box, and from that one very laser beamed topic I have branched off articles on extremely specific elements of that already specific topic. I assure you, no matter what your article is about, you can write about it more in depth in a new article.
As a writer you know how difficult it can be to come up with article content at times. If you've ever had writer's block you know what I'm talking about. There are several things you can do to make it through the writer's block phase. One of the most popular is brainstorming with a friend or family member. Another option is to rewrite the articles and blog posts you already have written.