It wasn't meant to be oneupmanship, just that you were deliberately ignoring the core of the argument. I could make an article about why NULL in C is a wonderful feature and how it allows such nice optimizations, or I could acknowledge that it has a great cost too. You basically said "There's no downside if you are as smart and experienced as me", but with respect to Javascript, much of the world (myself included) are not. Your argument came down to "people with sufficient skill don't make this mistake", which was definitional instead of actually addressing that the default behavior of an actual usecase was not sane.