R&B,
Ah, I think I got it now. Thanks a lot for clarifying. I was thinking about a sand bar when I asked my question. But I learnt from your answer that in the absence of a sand bar the wash at the back of the wave is the sweet spot. I never thought of this, as I've been reading up on how to read the beach from the wave and was thinking about sand bar only. Now I'm armed with another piece of very helpful info, thanks heaps!
JC