thanks everybody, it's the original poster of this thread here (I'm not Australian after all, just used their reputation to hide my own incompetence) I am loving all your comments, keep em coming.
i was out the other day in "surging" wind of 5kts-30kts surges with one other guy and he was getting up and planing ridiculously early compared to me as each new surge started.
he was on a little fanatic 80litre B&J with a 5.2 sail. me on my 121Carve with a 5.9m sail. Only other difference was his weight, about 20kg lighter. (me being 100kg)
The good news is though, once I got up I had top speed way above him, and could haul back his 150m lead in about 600m of water. Go figure? Any comments?