<p>“Every single professor at Caltech – except for about 10 division heads and high-level administrators – teaches courses virtually every year.”</p>
<p>Just to add to what Ben said, some of those people still teach every year too. I know Richard Murray, who was chairman of E&AS (Caltech’s largest division, no less!) still found time to teach CDS110 every year, not to mention spend countless hours advising the DARPA Grand Challenge team.</p>