Could This Be Why?

I was reviewing my sourdough documentation, specifically U.S. patent #US3826850A. The patent document describes the traditional San Francisco sourdough process. Excerpts below:

"The traditional method for making sourdough bread, otherwise 'known as San Francisco Sourdough Bread, is time consuming, cumbersome and impractical for most commercial bakeries."

Yeah, tell me about it.

"1. Maintaining a continuous starter sponge comprised of two parts (40%) previous sponge, two parts (40%) flour and one part (20%) water by rebuilding every eight hours or three times a day"

"Three sponge transfers a day and long proof times are necessary in order to obtain proper acid development and leavening."

Aha! This could explain why, after making all the right moves, my sourdough never turns out as deliciously sour as the old-school breads of yore. Keep in mind that these big sourdough factories in San Francisco and Oakland were turning out thousands of loaves per day, baking 24/7. They used a stiff starter which was refreshed every eight hours.

Baking 24/7, they likely used up the sponge as quickly as they made it.

I don't bake 24/7 so my starter sits in the fridge for days on end until I need it to bake. Therein lies the difference! The strong San Francisco sour was due in large part to the thrice-daily refreshment of the starter sponge. This may explain why my home-made sourdough never has the sourness I desire.

The only way I've found to achieve the old-school sour is to way overproof the dough, and of course this results in an unsatisfactory loaf.