really? There is more to aggressive/pushing the issue than hitting driver. Driver is arguable his best club, why wouldn't he hit it? Pushing it involves aiming at pins instead of bailing out and aggressive chipping/putting.
He may not have let up but he certainly didn't press the issue more than he had to... He is not stupid and wouldn't bring a double/triple into play with a large lead. But with the way he was playing, he could have shot another low 60s round yesterday if he really went for it.