Cutting the tenon with a router and edge guide jig. This is the setup described by Gregory Paolini. It works well, the only trouble is you have to flip the table several times while sneaking up on the final depth of cut. I recommend cutting only the first pass, then flip and check the fit. Cutting all the way to the shoulder will make it difficult to support the router. The jig is clamped in place, and stays put while you flip the top.
Double sided jig helps align the shoulders of the tenon. I made the jig from 7” wide mdf so it would not flex while routing the tenon.
Tenon haunches cut with a coping saw, allowing 1/4” for expansion/contraction at the outer mortises.
A groove was routed 1-1/4” deep in the breadboard end. The deeper mortises were cut at the mortiser with a 1/2” bit.
Breadboard ends fitted. A little chamfering and some slotted screw holes, and it should be set.
-- Willie, Washington "If You Choose Not To Decide, You Still Have Made a Choice" - Rush