When a player truly masters one shot their confidence is elevated. Once this happens they will discover their own style. Going through the TOI training isn't necessarily to specialize in the touch of inside, it's to open up the ability to synchronize our mind, with what's really happening at impact (TIP to cue ball).
If there's another way to do this I sure as heck don't know it, and I doubt if anyone else does either. The reason is complicated because it has to do with opening up a part of the mind that scientists don't understand.....the subconscious. This is where we have one of the few things that can be completely controlled......our imaginations, which is the foundation of creativity.
Pocket billiards is a very creative game that requires imagination, creativity and confidence....the TOI training is designed to strengthen all three at the subconscious level through repetition, not through understanding (you'll have plenty of time to understand it AFTER making the decision and committing for three weeks).
The issue with not favoring one side of center ball is the player can't tell if he (or she) puts a "touch" of left or right spin unintentionally. This means the players's mind can't synchronize properly and the level of confidence champion players possess can not be attained.
The key to developing confidence is repetition, with a focused purpose in mind.
Trying to hit the center of the cue ball at some invisible "contact point," or "ghost ball" is okay for those starting out - when a beginner, we must think as a beginner, however, when we make the decision to progress, we must leave beginning ideas behind.
For those of you that want to continue on this journey, I will start to expand on the deepest levels of TOI training. I'll be happy to answer any questions on the material we've covered so far, there are also a lot of free video's on you tube....Click Here for More.