On a website dedicated to “fighting ignorance,” I’m a bit astonished at this reaction. Maybe you could consider reading @Cervaise’s excellent post in this thread. It’s one of the best posts I’ve ever read on this board.
In short, no, the studies don’t all assume heavy traffic, and traffic is less intuitive than you might think. For one thing your well-intentioned act of merging well before the designated merge point may cause effects that you never even see, like if the person behind you reacts to your merge by tapping on their brakes thereby causing a slowdown that ripples backwards, possibly for miles. With a single merge point, this is relatively contained. With a bunch of random merge points, you can inadvertently create constructive interference (like with waves) and create much, much worse slowdowns.
You also might consider reading this book:
The prologue is entitled: “Why I Became a Late Merger (and Why You Should Too)”. 