Reply by Moron

If you run them first, then the two stiles need to have a “stop” rabbet. If you are a novice/intermediate woodworker and using dado blades, this can be dangerous. If you dont stop the rabbet then it leaves open spots at the top and bottom.

As others have stated, using router with a rabbet bit and bearing works for me and despite the fact that you shouldnt do the following…..I run the router back wards as this eliminates “tear out” and the final pass I run the correct direction, then knock thwround corners out with a sharp chisel.

-- "Good artists borrow, great artists steal”…..Picasso