I haven't heard of anyone using the pinking blades for cutting their blocks. Wouldn't the pinked edges make it harder to line up the blocks while piecing, and harder to get a <scant> 1/4" seam?
I have found that some fabrics ravel a lot more than others, and they're usually the fabrics with a looser weave. Homespuns do this a lot. I wonder if starching helps prevent the raveling. Fray check works for applique, but you wouldn't want to put it on every seam in a quilt.