Anyway, my theory is to use a lure that suits the size of the fish, and the type of feeding going on. I'm mostly talking snapper, and the various common bycatch.

I don't bother to use a 7" softbait over the summer feeding flats in the Auckland region, I use a 4" Z Man grub or a 5" Crazy Legs/Squid Vicious (Gulp). But I'm only realistically fishing for pannies, and up to 10lb at the upper end. Same with the shallow fishing over sand up in Northland. The prey is usually smaller baitfish, crabs, shellfish, prawns etc. So I can't see the point in using a 7" bait, even though the small fish will also attack them, you're more likely to get tail grabbers in my opinion. A good way to rip through a lot of big Gulps for little return.

And with the anchovy run, they are matched to a 3-4 inch softbait in natural baitfish colours. I'm sure the success of Kerry and MB with their small jigs is, in part, what the fish are feeding on in the area. I guess you could use a 7" or 10" and imitate the jack mackerel which are also feeding on the anchovies (and taken by kingies), but the fish chasing the anchovies are more tuned in on small bait.

But if I'm fishing off Kawau or the bigger fish spots in Northland, hoping for a donkey, I'll start with a 7" jerk shad, or a 6.5" Z Man Doormatadorz (which has incredible action in the water - and which is actually much longer if stretched out). The Gulp Nemesis (6") is another bait with a good profile and action, and accounted for my giant (77cm) trevally up in the Far North. There's always a chance of a fish up into the 75cm + class in those places - fish which are feeding on baitfish of various descriptions. And I've had bycatch of reasonable kingies for softbait gear. So it's a bit of a 'match the hatch' situation. One of my favourite Z Man colours - Midnight Oil - only comes in baits up to the 5" curly Tailz (as far as I know), so sometimes I put that on regardless of it not being the biggest bait in my bag. Something about the colour in the water, and the action, is just deadly.

I know there's a theory about going small in winter because the fish's metabolism slows down, and they are happy eating small prey. But going big when targeting big fish is the recommendation of Mark Kitteridge, and other such as Andre Kassal, who seem like pretty good experts to base my systems on. So I usually don't stray far from their approach.