Haven't done it on a quilt yet but have done it on bags. I don't join it. I just plan it to come up to a line I'm going to quilt along, sort of like quilt-as-you-go. It's never gone anywhere.
If you don't like joins and have lots of scraps, gift them to someone who makes bags or soft toys! I love finding small pieces of batting in my stash, always an inspiration to make something

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