Arguably it leads to an exacerbation of ones personality, not eradication. Its anything but relaxing.<quoted text>
But, mere "mindfullness" is not mastery over thoughts and emotions nor does it result in the transformation of thoughts and emotions into something superior to the ordinary or unregenerate processes involved in thinking and emoting.
Mindfullness does not put one in touch with the thatness of thoughts and emotions.
Mindfullness may have its limited uses in psychological therapy as a way of moderating rash impulses, anger, impatience and the like but it does not result in eradicting the seeds of the personality defects.
Noone ever claims it leads to mastery over thoughts and emotions, though. More like it leads to the ability to surf over them.
That all said, it is a powerful tool.