I like his point about focus in new companies. Do one thing, make it work. When it does, use your expanding group of resources to add on.

I don't understand his distinction between companies and features. If you have a product that can stand on its own, clearly a business can be built around it. But I don't think selling features that will contribute to a larger product is any less legitimate of a business. A hardware store can be a very healthy business even though a bolt isn't very useful until it's attached to something larger.