I may be breaking some HUGE batting rule - but i've always ignored the soaking instruction....All i have ever done is put the batting in the dryer with a wet towel and turn it on high....give it about 10 minutes and take it straight out of the drier and lay it out flat or with as few folds as possible. I do this right before i am going to sandwich the quilt. The steam takes all the wrinkles out of the batting AND it shrinks a little. I wash all my quilts before i give them away - so it gets washed then. I've never had a problem - so i am either really lucky, or it works.
PS... I always use the Warm & Natural product that allows 10" between the quilting.