I applaud Nielsen for trying to bring more data to the usability world, but man, the guy just doesn't bring any insight. All he does again and again over the decades is analyze a bunch of data which proves that well-established UI conventions work better on average than less common UI conventions.
However any designer or UI person worth their salt innately knows 95% of everything he has ever said, and applies it intuitively while balancing a dozen other issues which Nielsen pretends don't exist (branding, innovation, gameplay, etc). Nielsen's biggest achievement has been branding himself as a top-tier usability expert when in fact probably every high school in America has at least one aspiring designer with a better understanding of how people actually use computers.