Stuttering - Muscular or Mental Process?

In order to control my stuttering, I have to think about what I am doing now. According to "Self Therapy for the Stutterer," I "need to be concerned about what [I] am doing now that perpetuates and maintains [my] difficulty, not about what happened in the past.

The worse thing that I am doing, it seems, is trying NOT to stutter! "The mechanism of speech is so delicately balanced that in trying to stop stuttering, you may unwittingly make it worse." I didn't realize that I was doing that.

"The stutterer attempts to force the articulation of his words and speaking now becomes a muscular rather than a mental process." - Bluemel

It seems like a mental process to me! I am constantly thinking about talking and thinking ahead so that I can get around words that cause me problems.