Seeing Red - S6-E19
Trivia: Many gay and lesbian rights groups were angered by the decision to kill Tara. Joss Whedon has argued that the decision was made not because Tara was gay, but because she was involved with Willow; had Willow remained with Oz, he would have been killed instead. Killing Tara was a way for the writers to advance Willow's storyline and transform her into Dark Willow for the season finale.
Seeing Red - S6-E19
Trivia: This is the only episode where actress Amber Benson is acknowledged in the opening credits. This was done with the intent that the death of her character, Tara, at the end of this episode would be more of a surprise for the audience.
Answer: She has superpowers, ergo fast movement. The reason she outruns him so easily in "Touched" is that she stops trying to actually fight him and just dodges instead.
Shay