I'm not sure fans remember but he was an excellent OC for Romo. His offense led the league in quite a few stats.........
I don't think he was. I think he was a bit of fool's gold because great players could make his system succeed to an extent, but the limitations of the system, particularly the lack of creativity, kept it from being elite.
NFL history has shown that there are three ways to win a Super Bowl: Have a balanced offense and defense (both units in the top 10), have an elite offense or have an elite defense. I believe we did actually put together the components of an elite offense under Garrett (while neglecting the defense), but Garrett's offensive philosophy (it's all about execution) kept the offense from being elite.
I think this particularly showed up in his next stop, as New York's coordinator, when he didn't have to components for an elite offense, so he took one that had an upper limit of good and made it mediocre. Essentially, the Giants' offense showed how Garrett would have fared here without Romo.