what I have noticed is that, most of the move occurs on the open, and usually positioning is done, the previous session. then us market sentiment is used to gap the hang seng on the open. But after the initial gap, the local players do what they wish, and it can easily retrace the gap or fade the open.
From what I have seen SO FAR, I would agree. But I haven't seen enough--past data or present data--to warrant putting money on the line yet. There is money to be made trading the big swings in HSI, and also ES. There are also many smaller moves, but those are harder to capture, again, in both HSI and ES.