They use a bolt rig, with the sinker secured to the line, but that would leave the sinker trailing from the fish if the line broke off between the reel and the sinker. I use a three ounce sinker.
Nice fish. I don't have a whole lot of time to comment but I wanted to chime in on this part at least this morning.
A true bolt rig is designed to hold the weight tight when a fish picks up the hair, this is quite useful for hook ups and in snaggy waters where it is important to have the weight rise off the bottom quickly with a strike.
However, there is always some safety mechanic that allows the weight to slide off with a small amount of tug. Meaning that on a strike the weight would lift ..however if the weight came in contact with pretty much anything it would become a free sliding weight. Or depending on the rig fall off completely leaving the line intact ( ie safety clips )