and your note about color (=.dcp camera profile) profiles basically means that any "color" transforms (from camera's RGB numbers to ACR's internal working space) are happening after demosaicking as well, hence no matter what do you do and how do you create a profile (with or without Adobe's DNG PE - even if you type it yourself manually and compile using Sandy's DCP compiler/decompiler) it will not affect the demosaick itself (in camera's own RGB numbers, that what "the fundamental demosaic results" actually means)...
PS: about BayerGreenSplit tag - why this is not user accessible parameter ? I saw a numbers of cases when people long after ACR version release send you a sample raw file for you to correct maze artefacts... isn't it more simple to put it somewhere in UI in a camera calibration tab for example ?