i do not pre-wash batting any time-for any project! and i've made lots of jackets, totes, home dec items-
i purchase the batt that is best suited for what i am making- i can simply not even imagine the hassles involved in pre-washing a batt...that just seems---crazy to me- there are so many wonderful batts on the market- with different properties/fiber contents/ shrinkage rates/ quilting requirements- some are specifically made for clothing items- (they say on the package-good choice for clothing items)