When you are dropping straight through weedbeds, are you just yo-yoing the jig up and down?
kind of and most of the time, i'll drop it thru a hole (or make a hole) then shake it a time or too, then reel up and pitch to the next hole, i did stumble on to something several years ago and have had some succes doing this, fishing in milfoil or hydrilla take a white jig with a white trailer, drop it thru the holes and reel up till your on the underside of the canopy, then bump the jig upward on the roof of the canopy, suposedly it imitates a shad or baitfish eating at the bottom of the cover, i have also used alewife jigs and trailers, but pure white has always done better for me, if you try it don't get discouraged, you can fish a whole llloooootttttt of water before you find the fish but generally when you do find them they will be ganged up and be all good fish...
good luck hope that answers your question, sorry it took me so long too see it, been kinda busy[:@]