Are the miters to hold the corners together or through the corner horizontally? If vertical holding the mitered corners together I would say it should be a pretty good choice as the upcut gets rid of chips better than a straight bit. It may rag the edges a little but most of the grooves will be hidden in the joint. I would use a scrap piece butted to your good piece where you exit the cut to avoid blowout if possible. That would be hard to hide.
If they are horizontal splines that show on each face then the upcut may leave a rough edge on the slots that might be hard to hide.
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.
Last edited by Cherryville Chuck; 02-28-2019 at 10:01 PM.