I still think tearing is the way to MAKE sure that the GRAIN of the fabric is straight. There is a lot to be said for straight grain especially when quilting. ALSO, when you cut across the width of the fabric, you are already making the fabric less stable, SO if you want the fabric on the straight grain and do not want to tear you can always pull a thread and cut, HOWEVER if the fabric store cut it off grain as most of the stuff is these days, I hope you will include an extra 4 to 5 inches, because you can lose that much if you figure out that both ends are off grain.:)