I haven’t watched much of the series, and know very little about Curran, but one comment I heard from David Gower, yesterday, suggests that he thinks that Curran should only be picked if you know the ball will swing.
His comments were something like “Bowling at around 80mph, he is cannon fodder, but when the ball swings he is a different proposition”.
On a side point, it was good to see the Aussies waste another review, trying to get the LBW overturned. From what I remember, Curran had run the entire length of the wicket, in celebration, before the umpire even signalled out, so confident was he that it was plumb.