Golumless
A bigger deal out west.
That was the thing that worried me the most at the very moment I first heard of the ball-tampering incident. Warner and Smith are very different people: Warner is combative and extroverted, players like that need a fight and he'd more likely see this as a challenge to get back and would probably (marginally) improve from it.
Smith on the other hand was never too combative and was always a bit more introverted and more self-critical. Add in the fact that one of his biggest strengths was the concentration required to rely primarily on hand-eye and you can start to see where the rapid slide down the batting averages can come from: Mentally he's still trying to recover, something he may never do.
I'm not worried about Smith at all, he's evidently had the mentality to become the best batsmen in the world. He's strong enough mentally to come back, though will probably take a year or so to do so.
People overrate the introverted/self-critical side of things, especially in the case where someone has long shown they're in the top percentiles of mental strength.