And it's saying something that the worst of all McGrath's 200-odd innings spells (I was talking more match spells TBH) was an economy-rate of just 3.4 or so.
As I say, Steyn has essentially been on one long high for the last nearly 3 years. But no bowler can keep going with barely a bad game forever. Even at his worst, Steyn has usually got 3-4 wickets, even if he's gone for 150-160. But Steyn has had many games where he's conceded a very high economy-rate - 4-an-over, and more sometimes. It's only a matter of time before he has the odd really bad one. And as I say, when he has a bit of a bad patch - as all bowlers, inevitably, however good, do - then there could be some serious carnage.
I only hope it's next year rather than in the upcoming series against Australia because SA really need to win that series and Steyn at home could devastate Australia or anyone if he bowls as he has the last 3 years.