You are right in that it does show CG position.

The typical trainer uses a forward CG that ends up with a down load on the tail. It tends to give an airplane that has an exaggerated nose-up-with-speed-increase effect (our old contest rudder only airplanes were set up that way). For a beginner it means that if he gets out of sorts with the nose headed down and the speed increases the airplane will have some pitch recovery tendency built in. A more experienced flyer typically will not like it.

The second figure (for those of you that can see it) is the more aft CG location. The up load on the tail gives an airplane that doesn't have the exaggerated nose-up-with-speed-increase effect. It makes for a smoother more aerobatic machine.