I don't wash my jelly rolls. I've never had any problem with them .

I don't prewash - if its going to shrink - I want it to all shrink together and the even bigger reason....I'm lazy that way!

Never prewash. If I had to prewash even by hand I would never use JR.
If there is a mix of dark and light colors I use Synthrapol when I was the
finished quilt just to avoid any bleeding.