I was having a problem cutting tenons on my table saw because the rip fence I was using as a stop wasn’t square with the table. The result was stepped shoulders. So I came up with a tenon-cutting sled that attaches to my table saw miter gauge.
The sled is just a hardboard platform with a couple of wood fences. It uses a single point stop to gauge the length of the tenon. I drove a finish nail into a stop block and clamped it to the sled. Using the finish nail as a reference point for all the shoulder cuts results in perfect tenons every time.