I prewash everything - with one exception: Pre cuts such as 2 1/2" strips and 5" charm squares. I think it would be a nightmare if you wet those strips down and then toss them in the dryer. I just made a strip quilt that used a Robert Kaufman Jelly roll and strips that I cut myself from Moda Bella Solids from my stash. I washed it and there wasn't any issues with it. I think you are safe!