So. when you post on D.Buzz, yes it get put on the HIVE blockchian, but the posts get posted to the D.Buzz Community ( https://peakd.com/c/hive-193084 ), so unless you are subscribed to that community (hive-193084), or the content coreator went to another front-end like peaked and re-blog it to their main page or shared it to another community you are in, you would not see the Buzz from them... its like posting in a comunity, only people in that community will see the posts. :D
As for what constitutes a "proper" article, or what the main underlying use should be for this blockchian, that is a whole other conversation. 😉
I honestly don't know when it's shown where.
I use Peakd and LeoFinance for browsing me Feed and both show the D.Buzz posts from the people I follow, I don't think communities are relevant to either front-end? Peakd is just showing everything the people I follow post and LeoFinance shows everything tagged with Leo(finance).