Idk, I gotta say I have seen people lose a lot of corals from alkalinity swings, and from overly low alk. It is pretty obvious to anyone who doses that the corals use alkalinity. RE dosing, alkalinity is one part of a 2 part calcium buffer system - at the end of the day it is carbonates and bicarbonates bonding with calcium to develop stony coral skeletons, and the acid concentration in the water needs to be as such to allow that chemical reaction. If you have a mature tank with crushed coral or sand, and a ton of live rock (that is actually old coral skeletons and not concrete or something) you may have sufficient buffering capacity within the tank. Tanks with crushed coral or aragonite sand tend to have higher alk and pH absent dosing.
For corals to grow at their best, many chemical and physical conditions must be optimized. Dana Riddle examines the effects of varying levels of dissolved bicarbonates on coral photosynthesis and growth.
www.advancedaquarist.com
One thing not mentioned that BRS has been getting at in their investigates series lately is the effect of water flow having a larger impact on coral growth than even lighting. The more I observe my tank the more I believe there is merit to this as well. I have also seen videos and experiments to illustrate that as well.