Wow, what an interesting post. I know I learned a lot from it. Now I am worried about the quilts I made for my grandchildren. They were made with 100% cotton and though they were quilted closely, the kids were diagnosed with allergies. Now, their quilts are getting washed weekly, hot water, on an allergen/sterilize cycle (the new front loaders). I hope the tumbling rather than agitating is kinder to them.