Thanks fellow quilters. I appreciate your answers.
I guess one of the reasons I have not tried the pinwheel thing in the center is that I was slightly afraid to undo those stitches (that are needed to rip out in the center) in case it would come undone at that spot. I think that must not be a problem because so many people do it. How many of you pinwheel your centers and have any of you had trouble with the center becoming unstitched? I need to try that technique.