That would take this set to 26 keys. I can't understand why they would rather have no CMYW than have a couple keys not designed for the pack "missing" that they probably have already in some other form or could get at a later date. Oh well Korean logic I guess.
I think you misunderstand something, Korean's CMYW still have the essential keys for 1.75x, 2.25x & 2.75x shift, 1.25x 1.5x for ctrl & alt.
They are more tend to have a set that is more "useful" for ANSI layout since they almost not using any ISO layout in their community.
Thus they decided to replace 1.25 shift keys and 1x ctrl & alt keys with 1x 1.25x win & fn keys.