i wash absolutely everything in hot water with like colors, towels & sheets usually, then dry on cotton...so any running or shrinking is done before i cut it.
i had a fabric in a finished quilt ( all purchased at the lgs) that ran and shrank crookedly (like it wasn't printed straight) in the quilt...
i never cry, but i sat next to the washer & cried that day....that'll never happen again!