I was just having a dig at the 3-6ft reference.....it's a pretty big variation in size. The usual terms range around 2-3ft, 3-4, 4-5, 4-6, 6-8 etc. The most common gap of 3ft kicks in at 12-15ft because then you're getting into the same scale variation you experience at 4-6 or 6-8ft.
In my experience, it's pretty rare to have 3ft waves rolling through with 6ft bombs in the water as well, except in the lulls.
And its all part of the fun we southerners love to poke at Queenslanders because we're just jealous we only get a couple of months where shorts are an option