Here's my theory on the grading system, FWIW:
School X changes grading system from traditional ABCDF to "no-grades" system High Honors-Honors-Pass or whatever the names may be. At first, employers don't know what to make of this cryptic grading system, but after a while they figure it out and start calculating some type of index number instead of a traditional GPA. Then the school changes the system again, or decides not to compute GPA or rank, or something equally silly. Employers can figure it out.
But, if you go to Yale, it doesn't really matter...you can probably have your pick of jobs, regardless of your all Pass report card.