Just to clarify on my other post.. when I say to add a 1.5 inch of
hardwood to the front of the 3/4" shelf, I mean that the top 3/4" of
the edging will be fastened to the shelf, and the bottom 3/4" of the
edging will hang down. This helps resist sagging.

After you glue the hardwood to the ply, you can put a 1/4" roundover on
the on the hardwood edging. I do this because I think it looks nice.