Skadoosh, one other nice thing about Tai Chi - a lot of its moves are derived from fighting techniques. A guy I used to train with in Fayetteville, NC, is a Tai Chi sifu, and he could take a lot of their slo-mo moves and apply them very neatly in an aikido setting. Some of the step and balance moves work wonderfully when used for a sweep, for instance.
And you might not believe the sweat you can work up, keeping balance while moving slowly. In fact, moving quickly will often mask poor balance points, while moving slowly will expose each as it occurs.
Slow is hard - but not high impact.