One issue I've run into when I looked into strategies like this is that bonds have been an incredible investment over the last ~40 years. Sure, they haven't bea

One issue I've run into when I looked into strategies like this is that bonds have been an incredible investment over the last ~40 years. Sure, they haven't beaten the S&P500 straight up, but their volatility and max drawdown has been so good that you could have used leverage with them and gotten a portfolio that easily beats the S&P500 with as good or better volatility. The problem for me going forward is that these returns for the last 40 years have been do to falling interest rates. Can the rates keep falling? A little bit more. Will they go negative like some other countries? Maybe? But at some point I have to wonder if this strategy is still viable.