In other words....yoga

This article in the NY Times talks about habits:

...don’t bother trying to kill off old habits; once those ruts of procedure are worn into the hippocampus, they’re there to stay. Instead, the new habits we deliberately ingrain into ourselves create parallel pathways that can bypass those old roads.

But they might as well have been talking about yoga.

From Desikachar's Heart of Yoga:
The conditioning of the mind that lets it continually take the same direction is called samskara....Through yoga we attempt to create new and positive samskara rather than reinforcing the old samskara that has been limiting us. When this new samskara is strong and powerful enough, the the old, distressing samskara will no longer be able to affect us.

back to the Times story: Ms. Ryan and Ms. Markova have found what they call three zones of existence: comfort, stretch and stress. Comfort is the realm of existing habit. Stress occurs when a challenge is so far beyond current experience as to be overwhelming. It’s that stretch zone in the middle — activities that feel a bit awkward and unfamiliar — where true change occurs.

Again, from Heart of Yoga: When we practice asanas we carry out actions that are not determined so much by our habits, and yet still lie within the range of our abilities. We are no longer so bound by our habits.

Christopher Isherwood and Swami Prabhavananda also write about samskaras in their commentary on the Yoga Sutras:
Expose the mind to constant thoughts of anger and resentment, and you will find that these anger-waves build up anger-samskaras, which will predispose you to find occasions for anger throughout your daily life....Let us never forget, however, that just as a sandbank may shift and change its shape if the tide or the current changes, so also the samskaras may be modified by the introduction on other kinds of thought-waves into the mind.

So, there you have it. From ancient India to the NY Times, experts agree. We can't get rid of our old/bad habits, but we can introduce new, better habits by moving outside of our comfort zone. With persistence and practice, you can teach an old dog new tricks.