Does Buy the Dip Work?

A reader asks: I am roughly 100% equities, a mix of S&P and global stock indices. I have now ridden out the GFC, COVID and other downturns and trust myself not to sell in the downturn. My wife and I have had good returns but I was wondering if holding a portion of stock in bonds as dry powder to invest in downturns wouldn’t be a better strategy. With fixed income earning decent returns now it may make more sense...