He'll work it out eventually, yes, but this last year he really struggled in ODIs I thought. His overall average looked OK in 2012 (35.00), but it's propped up by 2 100s: 1 of which was a real struggle (100 off 140 vs SL in the finals last summer).
His scores last year:
0-19: 9
20-69: 13
100+: 2
Just hasn't really learned how to build an innings past the first powerplay, hence a lot of those 20-69 scores. I count 7 or 8 dismissals to spin last year too - a high percentage for an opener who hasn't made a lot of big scores. I feel he panics when spin ties him down early, and can't switch gears easily enough when the fielders get pushed back. Too often he keeps wanting to hit boundaries, particularly vs spin.
As I say, I think he'll get there. Some games at home will help, and every ODI innings gives him more experience.
Don't you think he is going Sehwag's way? As we have seen Sehwag playing some tremendous knocks in ODI but it did not come very often. Sehwag is very successful at Tests and T20 and I have seen the same thing with Warner but somehow they just find it difficult to get going in ODI's.