I believe the best use of a sharpening system is to help the user understand the meaning of the feedback he receives while sharpening knives. So when he feels fairly confident, he can entirely switch to manual sharpening and continue improving his skills.
Now, for more kinesthetic people, a sharpening system might not be of much use due to their already increased hand skills. But, for "not so good with hands" people, I feel that a system can help speed up the learning process.