HI Pasta,
Missed your reply.
I have used this a number of times and works really well of piers or rocks with deeper water or when the waves break past the rocks.
Have also used of the beach when there is a small swell and deep gully close in.
Basically all you do is take one of the big wooden floats (you get them in red/white/yellow).
I am horrible at drawing, but will try and explain using the traces you just described.
Complete the traces as you explained above, but do not attach your clip.
Slide the "bung" onto the leader part of your trace. Ensure that you place some beads on both sides to protect your knots!!
Connect your trace to your mainline/leader with double figure of 8.
The bung can now freely slide up and down your trace, but is stopped by the fig of 8 and will keep your bait swimming in the upper water collumn. the depth will be varied according to the length of your primary trace!
I have seen garrick and big kingies taken with this method. We also used it very succesfully with torpedo scads in R Bay harbour targeting sharks (then you use steel!!)