yeh I wasn't expecting much either, based on what I saw on the jetstream map.. nice bright blue area over sydney. But like you, sucker for punishment. Chasing sucker holes for 45 minutes wasn't much fun.. but during the cloudy times I processed some of the Mars avi's from last night
The jetstream maps seem fairly accurate to me.. but it's not 100%.
That is, if there's no jetstream it doesn't guarantee good seeing.
But if there is a jetstream it almost always means average (or below) seeing.