It's basically putting the weight below the bait. The weight will hit the bottom first taking the weight off the bait. Then if you give more slack line the bait will fall slowly the last ft or so to the bottom. That slow fall the last two feet or so makes it more tempting to the bottom hugging fish and gives them more time to decide to bite. As compared to putting the weight above the bait making the bait fall faster with a thud into the bottom.

It's been around for many years but it's been rediscovered by this younger generation and given a fancy name.

We use to call it tightlining for crappie with a bass rod and reel. You let the bait down to the bottom and reel up two turns. Basically its doing the same thing we did years ago when I was only 8 years old. You are letting the bait sit above the fish and letting it sink slowly to the fish or just hanging it above the fish's head. Of course this works if the fish is on the bottom of the lake. But you can still hang a bait in front of a fish if you know the fish's depth and the depth of your baits. That's were good modern sonar comes in handy. That and a long rod that helps you measure out how much line you have out. A good 12ft rod comes in handy when the fish are suspended at exactly 12 ft down from the surface. Just let out enough line to get the bait to the end of your 12 ft long rod handle and you have 12 ft of line out from the tip end of the rod to the other end of the rod. Now fish with the rod tip right on the surface or let out another foot of line and fish 1 ft above the surface. Jig a bit up and down and you will cover the 11ft depth, 12 ft depth and even 13 ft depth. This way you can present the bait at the exact same level as the fish.

Float and fly is another method that has been rediscovered by the younger generation and giving a new fancy name. It's nothing more than crappie fishing with a slip bobber. LOL This method is deadly for the same reason as Drop Shotting. It puts the bait at the same level as the suspended fish and also gives the jig adds action as the bobber dips up and down and sideways with the winds and waves. It's effective on Large-mouth bass too. I have caught dozens of large-mouth bass while crappie fishing with a small 1/16 oz soft bodies jig and a slip float and bobber stop from Thrill. Even catfish will bit this setup at times.

Hope this helps.

Think of a weightless worm that's cast out and allowed to sink slowly to the bottom. This is something the fish just can't resist. But it would take a long time to get the worm down to the bottom in 30ft depths. So you use the weight at the bottom of the rig to get the bait down near the bottom fast and then let is sink slowly under it's own weight when the lead weight hits the bottom first. Once the lead weight is on the bottom there is nothing pulling the bait down anymore and it sinks slowly on it's own accord. That's where the fish are sitting right on the bottom at times.

Drop shotting is actually a deep structure technique and you will need a good topo map to work it effectively. Or know exactly where the fish are in the deeper waters. Ends of points or old now flooded river channels in reseviors are prime area to use the drop shot method.
Regards,

Moose1am