I recently bought fabric at JoAnn Fabric and the clerk tryed to
make the fabric staight however if you want a true straight cut
you need to tear the fabric. I have even done it with slipcover
fabric. when wanting a true (straight of the fabric) piece.
We loose lots of fabric just trying to make our pieces square or
straight so I guess it is up to the user what you do.
Flo from NNY