This is poor advice to give for a landing approach. You should use your elevator to keep the plane level, or slightly nose up, on the approach. And then use the elevator to flair the plane out just before it touches down. Flairing the plane out should stall the plane so that it quits flying and touches down with no more lift. While on the approach the speed should be controlled with the throttle. Also, the amount of lift is also controlled with the throttle. When holding the elevator in a level attitude applying the throttle will slow the rate of decent and lowering the throttle will cause the plane to come down faster.

While the first part of Garfields advice is the same as mine, using the elevator to control the attitudue, the second part could lead to some real problems. Following the above advice is not recommending as if you nose down you could put the plane into a poor attitude that may not be able to be recovered from and causing a crash. And raising the nose could cause the plane to stall out at a low altitude that you may not be able to recover from causing a crash.The elevator should be held pretty much at a constant during a normal landing approach, and the throttle should be used for your adjustments.

While the CGdoes affect how the plane slows down, it's not "the trick". Learning to slow the plane down and fly at slower speeds is going to be the same regardless of where the CGis located. The issue here is more about learning how to properly fly the plane, and less about how the plane is set up. As you are still learning to fly this plane your best bet is to put the CG right in the middle of recommended range and learn to control the plane with it set there. Once you are comfortable flying the plane, and can slow it down properly, then you can start experimenting by moving the CG and seeing how it affects the flight of the plane.

Ken