Doug, you usually apply 3 coats of mud, each one with a wider knife and all starting with a little bit of a mud crown over the tape. You also use a wider knife with successive coats. As you then sand this back, you end up with a very thin crown over the tape but it’s over such a wide area that your eye can not see the crown from in front. You do the same thing for inside and outside corners as far as blending the crowned part into the wall, but these have kind of a “fold” at the corner for the mud as well as the tape. OK?
Henry in MI