This method is not a viable framework for investment decisions. It creates artificial precision through inconsistent historical comparisons and ignores gold’s own volatility and non-monetary role, as well as offers no actionable mechanism for real-world trading.
There is no way to trade the SP500 directly using gold, it’s not a functional modern currency on it’s own but rather a commodity. It requires an intermediate currency.
So interesting idea, and perhaps one some central bank of a country should create again, but not useful other than in abstract.
I get where you are coming from but gold as a commodity is special since it is most often used by a large margin as a value store. Even in jewelery people insure it do to the value it holds. Its true that it has its own volatility but I would argue the volatility seen is more about currency volatility than gold volatility. I can’t think of a more stable indicator of value.