So it's possible that Root might get that hundred in Australia finally. But even if he does, that's his 9th Test in Australia, on second attempt.
Given how Smith and Kohli have really set the bar very high in the current season, does Root still belong in this list?
Think of it this way. Look at how people rate a Pujara or a Mahela or a Yousuf. They are considered below the best of their times precisely for this factor. Even if Root gets that solitary hundred, and that too after the series is well and truly surrendered, is it really enough?
Kohli got a hundred in his first series in Australia, 4 in his second
Williamson struggled on his first tour here (in a 2 match series which is an important distinction because Kohli also failed in his first 2 tests here) but came out with back to back hundreds on his second tour in the first 2 test matches
Right now for me, Root does not really belong in this category.
Tier 1: Smith
Tier 2: Kohli, Williamson
Tier 3: Root, Pujara, Warner, Azhar.