:happywave
the thing about sydney diving is that if a site is blown out, there are always other sites available for diving (unless its a total blowout like 5mtr swells ect)
so - if Kurnell is blown out, Bare Island is a good dive and visa versa, if they are both messy, Shelley Beach is good and we have dozens of dive sites from sydney to 2hrs north and 2hrs south so we are very lucky
the thing about sydney shore diving is that most times you have to walk with your gear to get to the water - could be a 100mtr/300ft walk for most sites. i can do it (and almitychild) and im not in great shape but i do know some vistors are a bit put off by the idea
i think only Kurnell is tide dependant but it can be done on an outgoing tide-you just have to do it right
as far as your "this time of year" bit - the blue water comes in and the viz improves... but for the past couple of weekends we've had swells that took alot of people out of the water
planning on a visit???
cheers