Here is your challenage if you should accept; I am looking for a way to make recesses for my deck lines. I would like to use the brackets that most composite type yaks use, but would consider other ideas. I have thought about using a core Box bit, but that won't give me any slope on the sides for drainage, same using a dado blade on the table saw. I prefer recess mounts because of less things to get caught on in a self rescue. But need strong lines for the same reason.
So get your engineering minds working, sharpen those pencils and give me some ideas.