I agree with Chris’s definitions of VMC(ourse) and VMG(ood). In my book, the replayer is plotting VMG all the time. That’s what it says it is doing, and that’s what it is doing by the commonly accepted definitions of VMC and VMG.
What we are asking for is velocity toward the mark. I don’t know what to call that other than VMC. Whatever definitions you use, they should be consistent no matter which direction we are sailing.