"If you’re sane only about 25% or so of your gross income is subject to the results of real estate negotiations. Close to 100% is subject to the results of salary negotiations. Thus, your salary negotiations are probably going to be the most important financial decisions you will ever make."
That's pretty irrelevant really, what's relevent is the difference it can make. First, if you negotiate a 20% discount on the 25% you're doing better than negotiating a 1% pay rise for the 100%. Second, a negotiated salary recurrs annually, it's not a one-off sum. So yes the conclusion is right, but for the wrong reason.