I just made a table runnner using pre-washed batiks (I washed them 3 times). Well, when I steamed the seams the dark still bled onto the light right on the seams (if I had used Harriet Hargrave's test to wet, put it between paper towels and put a weight on it I would have known to continue washing). I will be throwing the top in the wash with come color catchers and see if I can get the color out.
These were LQS batiks and I did not wash them enough -- I would advise washing your batiks.