If you had the perfect grapes, would you add anything to the must? I’m saying a red wine must with 25 brix, 3.5 pH, 6.5 g/l TA, native yeast like D80/D254, perfect nutrient level, fruit with no bacteria, etc. Would you not just crush the grapes and let the wine make itself? That is what I would do. I read about all these additives that people use and have wondered if the additives are being used to correct a grape deficiency, make a certain style of wine or just being added because someone or some marketing piece said they should?