In the words of my very wise Japanese teacher, "practice no make perfect, practice make permanent."
As stated above, the human brain is greatly capable of engraining patterns into itself and becoming adept at exercising common sequences.
That's wonderful because it is the strength of human intellegence, the one quality that we are desperately trying to mimic in artificial intellegence research, the one quality that eludes our understanding.
But this very quality can harm us as well. If you practice the wrong procedure, you can be assured that it will be at least twice as difficult to unlearn it.