Before you make the mistake of making your RGB and W separate fixtures into one fixture, know that the direct control is only part of Scenes.
The effect editor in Timeline still does not support direct color control of additional parameters. This update is great if you can get away with only using Scenes, but not what I expected when I saw "Direct Color Control" in the heading of the Release Notes.
Yeah I was sad about that too. Going to try an RGBA fixture to see if it integrates better now with the adjusted math.