"There's risk in releasing the Australian results first because it creates a benchmark of expectation. If the US results come in close to the Australian results then the US results will get a big yawn from the market. And if they come in lower, even if they're within the margins for statistical significance, the market is going to smash us."
Pretty sure ASX rules say that you are not supposed to withhold market sensitive information out of fear that it will be market sensitive.
