User blog comment:Dragonjet/KC3改/@comment-70.83.39.226-20150928183422/@comment-26091666-20150929035105

It:
 * is not what you would think it would expect to see it as. That is it would look really ugly and may even leave "artefacts" on the screen.
 * would introduce a lot of unnecessary bugs for the implementation, not to say when a user wants to add that in the future by themselves it may involve lots of effort for minimal amount of fancy looks. If you were to leave that to the devs to deal with the new CG that is yet another unnecessary burden.
 * also makes KC3 Kai more liable to the user getting banned even if the CG are overlaid on top of the original CG and not the actual editing of the stored data within their cache.

Already Dragonjet has already expressed no interest in making ShimakazeGo to work with KC3 Kai. You can sort of imagine what the outcome would be like if KC3 Kai devs were to now implement that.