It seems that Fold down levers have always been around and they can be found on just about every hunting accessory that you can think of. The most common are the bolt and handle ones but there are many others. What do they all have in common? They allow for scope movement without having to remove your gun from the carrying case. So why is this important?
If your target is at 100 yards or less, you have very little room to make an accurate shot and to be accurate means that your shot will wind up on the target and be on target. With a scope, there is the option to move the lever over to the right to lock in the scope and to move it over to the left to wind up the scope. Without the lever top moved up or down, the scope could not lock onto the target because it would be hitting nothing.
This is important because it gives you a measurable advantage, but only if you know how to use sighting in a scope properly. When I shoot, I prefer to cock the rifle in a steady motion without moving the lever itself all the way down. If I did that, I could cock it too early and miss a target, or if I went to far and missed a target, it would hit the floor or wall and then I would need to drag it back up to where I was. With the lever in a stationary position, I can have my shot come off even faster than normal.
In addition, knowing how to use the lever properly allows you to get more out of your shot. For instance, with a pistol, it is very difficult to hold a good long shot unless you are handling a long coil. With a scope, you can have a much better sight line if you can pull the site down all the way. This means that you can have a better shot placement and you can place the shot further out, which helps the wind out.
Also, when you are shooting from on low, the leverage of your wrist muscles gets a lot better. This is because you can lift your arm down so that the joint will not slip. If you are on high, however, the leverage does not make as much of a difference, because you cannot lift your arm as far up to prevent it from slipping.