If you figure that one out.. please patent it... and let me know. There are some things that you can do to make your lures catch a little less weeds,( like slipping a small squid skirt over your snapswivel or trolling lead..) I have heard of guys using rubberbands in some fashion over the hook, to make it kind of weedless.. but havent tried it.
Knowing what a lure normally feels like when trolling clean goes a long way towards helping weed free trolling. You can often grab a rod that has some weeds snagged on it and clear them by giving it several hard, swift yanks. The trick is knowing when the weeds are off. The hootchie type squids are great for streamlining a swivel. Plus they present a prey, predator illusion.
Cleaning lures while trolling is probably the most frustrating thing associated with offshore fishing. Lures that stay on the top don't catch as much weed as the plunge and pop types. Like deep sea gull said, hard jerks sometimes work but it gets old. Just keep taking turns doing the cleaning. That helps a little bit. The big problem is that you never catch anything if your dragging grass on the lure.
I've seen people get so sick of it that they finally get on the flybridge or tower and shoot at the lures with a rifle. This is a desperate move but it helps with the frustration.
If your trolling inside 50 fathoms try the dolphin lures (generic name for this type of lure) these are the cheap lures that come prerigged with about 15" of cable a 6/0 or 7/0 hook and a cheap swivel. cut off the cheap swivel and crimp on a ball baring swivel. the plastic skirt has a molded in flatened head and a small bullet weight with feathers under the skirt. they come in assorted colors and will flip over the weeds 95% of the time. I deck hand on a friends 6 pk boat and these are the only lures put out when the weeds are thick.
Past 50 fathoms we only put out heavier rigs, you have no choice except to watch your lures and clear them as they snag. and yes 8 hrs. of clearing weeded lures is a drag.
speaking about all this weed......... if y'all've never tried it when the grass is rafting up real good making for wide weedlines or big rafts of weed, take something like a really big chrome pencil-popper with the hooks removed and cast it way up in the weed reeling it out across the top o'the weed as-fast-as you can........
i've done this and drawn lotza of dodos and other stuff out from under there for someone else to cast at with hooked lures, and even done it whilst trolling to draw'em into the spread
just remember there aren't any hooks in it......... so don't forget that and jerk it real hard if it gets struck................ you might just catch-it-in-your-teeth
now that i've just finished typing all that rot, it gave me a thought..... (did y'all hear that 'klunk!'?).........
just-for-the-helluvvit, i might rig something hookless with with some unravelled nylon rope to see if i can't catch sumpin'........... (when trying to tease'em out from under grass)
everything out there's got a mess o'teeth, and i've used hookless lures with shreaded nylon to catch freshwater gar over 100lbs............. it just gets so tangled up in their teeth that there's nothing they can do to spit it
try using a peice of 300lb mono or less (about 8 in) depending on hook size and pinchig it end to end forming a u or tear drop then attach it below the hook eye with 1 minute epoxy and a couple of wraps of light mono. after the epoxy kicks then lightly heat the weed guard with a hair dyer or flame to curve it upward so that it blocks weeds from hitting the hook. I use hard mono for the weed guard because of it stiff qualities I also try to down size to spro aussie style swivels to deter any snags and I do away whith the snaps an go to just the swivel if I am in heavy weeds. this really helps get those hard strikes form those big mahis and cobes that lurk in the weeds. but eventually you will get in the weeds