We've probably had two types of thick vegetation in mind discussing this. In my case locally it's hydrilla that had topped out, then the lake pool dropped about 7 feet. Now the tops are laid over. Animals are walking all over it. Mice can make it fine. Soon ducks will be wandering on it. The slop runs from about 3-5" thick. It takes a piercing force to penetrate it. The operation is normally good over a ditch below.
Lily pads in other lakes in Arkansas had grown to maturity, then pool levels dropped, shoving pads together. That's much tougher. It takes a sharp pointed sinker no less than 1.5 oz, launched as high as possible, shot through the tough leaves.
I tried some of the screw-in heads, and Senkos, but too many times the plastic gets left behind next to the hole, even when glued on. Senkos are just too tender for that. It takes a stiff plastic to survive it, a good choice the Mann's Hardnose.
It's a bit more trouble than I care for now, though some big bass are coming out of those mats. I move out past the last visible weedline and look for newly emergent hydrilla where bass like to bury up in foot high weeds.
Jim