You may want to concentrate on smoothing/correcting skin weights for the robe instead.
Although given mesh density, I gather it might be a drag for the smooth brush.
Not to mention the skin weight tools got completely broken by one of the updates to CC.
Blender is strongly recommended for this type of work.
And then it definitely needs physics to drape correctly while animated.
Physics is even more important for the robe type cloth than skin weights.