My chair railing, in various places around the room, is going to be
butting against the casing around my doorway, around my closet, and also
around my windows. The chair railing is a little more 'raised' at its
highest point than the casing is, so when it's flush against the casing,
you can see the end grain.

What is the most typical method for installing the railing at these
junctures? I'd imagine you don't just butt it flat against the casing
and allow the end grain to show...

Do I just miter a 'return' at all of these locations? If yes, should the
return basically be right up against the casing so that, in effect, the
outermost edge of the return/chair railing is touching the casing, and
then goes 45 degrees back from there (if you can picture it...)?

Thanks!!!