A really good way of linking what the surf forecast say and what actually is happening is to go to a beach on those days and compare fiction to reality.
In the olden days of surf you watched the swell looked at the synoptic charts, sacrifced virgins into the volcano, and threw burning surfboards off cliffs.
The net changed all that which is why 2000 web readers turn up at your local on a forecast.
Think beyond that and you will snatch some good uncrowded surfs against the odd.
Snapper, Kirra, Noosa,Malibu and Bali excepted.

I've taken up troll hunting just for fun, instead of a rifle I'll just use a pun! 冲浪爷爷