If he'd been appointed 10 years ago, recommending Shuttle/ISS be shelved and we get on to Mars quickly, those recommendations wouldn't have gone anywhere at the time.

Back then, we had not yet realized what a dog ISS would be, or how tough it'd be to keep Shuttle flying safely (or just how risky it had been from day 1). Contractors were right in the middle of building the hardware, the astronaut corps and JSC saw it as their future, etc.

There certainly were visionaries, both professionals and peanut-gallery types like us, who saw the future and worried. But even if Griffin had convinced Clinton, NASA would have been in full-scale revolt, and I very much doubt Congress would have gone along. THis path is still controversial today, even though we've seen the problems with Shuttle/ISS, and even through we're only arguing over the difference between retiring Shuttle in a few years or several years, and whether to leave ISS 25% or 35% incomplete.

ISS probably had to be killed by 1990/91 at the latest, after that I think we pretty much were destined to build and fly at least some hardware before it could be considered a failure.