I tried that not long ago to build a louvered grille for a gable end on a house to ventilate the attic but I did everything on a table saw. I made the grooves first with a dado set set and then tenoned the ends of the louvers by running them vertically over the saw. I probably posted that around July. I found that to be much faster than trying to set up for the board thickness.
Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.