I could be missing something but I find this article a little ridiculous and devoid of any useful information.

I work for Atlassian. It's a $100M business. It wouldn't fall into either category. We've gotten there by selling a lot of software over the internet. We spend hardly anything on customer acquisition. There is no viral effect to our products.

Another successful business I can think of off the top of my head is ZenDesk. They have to be approaching $100M. Their main sales channel is the internet (low customer acquisition). They have zero viral effect. You either have X support staff or you don't therefore you will need an X-user ZenDesk license.