Personally I never really got on board with the downhill skier tag per se but I definitely thought his stats flattered him in 2011-2012, especially because I was noticing he was coming in at 3/lots and absolutely murdering attacks and ending up 70* off 50 or something. So it wasn't so much a case that he wasn't necessarily any better or worse under pressure than comparable batsmen, just that he was putting up incredible-looking numbers without really putting up the sorts of innings and distinct performances that Amla, Smith, Kallis etc were putting up. The last series down in Aus epitomised this - he did not a whole lot right until the very end where he carted around an attack that was frankly already consigned to an absolute flogging, and as a result of that innings his series figures looked fine whereas up til then they looked fairly ****. Ironically, the 30 he scored in Adelaide was a far, far more significant innings in terms of winning the team the series.
He's rectified all this to some extent in 2013-4, particularly with the way he batted against us and his innings in the Steyn-bopping-Shami-for-six chase (and to be honest I always thought he would once he got the opportunities), but I definitely felt that he was a rung below Clarke, Amla, Sanga etc etc for that reason, because they were playing seriously memorable, series-defining innings. The Amla comparison is particularly telling because to an extent it nullifies the "he doesn't play enough" point - Amla has played just as many Tests in that same period and pulled off some ****ing amazing knocks and series-winning/defining performances along the way (vs us in 2011, vs England the next year in particular). And I know this is getting off-track, but this is why I was so surprised that so many people would take ABdV over Amla in that other thread; it's very clearly the other way around for me.
TL;DR be careful when you rate batsmen based on raw stats, because samplesizelol and quality > quantity.