Answered by our resident kayak fishing expert and avid lure fan, Stephen Tapp
A. I use distance separation to avoid tangles. I make a point of running the distant lure twice as far back as the near lure, the near lure will always be the deeper diver of the two.
To allow me to vary the lengths for the conditions of the day (eg. when chasing tuna: shorter on glassy days, longer on rougher days) I tend to work in down-wind "paddle strokes". My most general purpose count is 20 paddle strokes to the near lure, 40 paddle strokes to the far lure. By carrying out the deployment down-wind I avoid risk of fouling the rudder or deck fittings if I have to stop paddling, and I also ensure I have the lures far enough behind the kayak (if paddling up-wind considerably more paddling will be required to cover the same distance).
I also run my lures "line astern". In other words I have the rods in dual/parallel rod holders in front of me, but I don't have them angled outwards (I rely on distance separation to avoid line cross-ups rather than spreading rod tips apart). To my way of thinking this offers a number of benefits:
1. It's not uncommon for a lure to go out of tune and run to one side or to start pirouetting behind the kayak. It may have picked up a tiny piece of kelp on a hook, or it could have been damaged by the previous capture. Not relying on spread for separation means this rarely if ever causes cross-up issues.
2. By using distance separation I can execute the tightest possible turns to chase fish, especially useful when targeting snapper, but also valuable when working to windward of tuna activity. The trick is to ensure that for every 90 degrees turned, you paddle the same number of paddle strokes the rear-most lure is behind you before executing the next 90 degree turn (one of the reason I count paddle strokes when deploying lures). Since using this technique I can't recall having crossed lines as a result of executing a turn.
3. In the rare event I think I have a cross-up all I need to do is execute a shallow turn and any twist in the line will run up to the rod tips (because they're only separated by around 100mm) where it can be seen and corrected.
Once hooked up I generally make a point of clearing the near lure first (whether it has the fish or not) unless I've been paddling up-wind. If I've been trolling up-wind I always clear the lure that isn't hooked up first to minimise the risk of being blown back over it and laying excessive slack line in the water.
In the event of a double strike it's always the close lure I deal with first.
Trolling lures Q&A session with Stephen Tapp
The art of trolling from a kayak
Trolling hard body lures for Snapper