What a relief.That's nice, but not necessary, because the laptop is totally stable when overhanging the front edge of the desk.
I think I was just being OCD about having everything line up.
I could imagine 125 years from now watching the grandkids of the "Antiques Roadshow" furniture twins telling some disappointed grandkid of Jenny: "Well, it would have been worth three billion yuan at auction if some OCD DIY'er cheapskate hadn't cut out these partitions!"