I decided to run some test to visually observe the fermentation growth rate at various starter to flour ratios at constant temperatures over time. If I don’t document things they are typically lost in my memory bank. It seemed best to post this to the forum rather than my BLOG because I thought other bakers may be interested now and in the future. Post on the forums are more easily searched.
The images below are shown once the starter has reached maximum height. I will attempt to mark each starter vessel at 12 hr intervals. These test will only serve as a relative reference. Sourdough cultures are more art than science, IMO. Various starters and even the same starter can/will act differently, depending on it’s activity at any given time. Hopefully a ballpark consensus can be drawn from the test.
The Test
I estimate that a 30-50% rise (target height for many artisan breads) on the starter below would take place between 18 and 24 hours. If these test turn out to offer some approximation of bread dough growth over time, it should prove beneficial. The larger mass of the bread dough should be expected to ferment more quickly. But the fact that the starter is not hindered by any salt may offset things. At least I hope so.
It may prove beneficial to be able to bulk ferment the bread dough at a constant cool temp for a predetermined time. Unexpected results may result - stronger dough, acidic flavor, more easily shaped, maybe pre-shaped or shaped prior to BF? Without test, who knows?
Can questioning ever be a bad thing?
Retarded Starters - Retarded Starters - Retarded Starters -
The starter below was mixed @ 70% hydration and had a 20% innoculation (1:(3.5):5) using BF. After the starter matured, and while it was still cool, the dough was extremely extensible and showed strong signs of strength. It is probable that this is due to the cool dough. Will enter the final observation after the dough has normalized to RT.
The lag time, the duration of relative inactivity was a full 24 hr. It looks like a 30-50% growth took place @ ~36 hr.
The image below was mixed 1:3:5 - 80% BF + 20% Whole Rye. It was placed directly into the retarder, which maintained 50F.
Notice that the starter above matured at the same temp in 60 hr and the starter below matured n 16. Is it possible that the 20% Whole Rye made that much difference? Sometimes (maybe often) test serve to teach me what I don’t know. 
Since most bakers rely on their refrigerator for retards maybe someone will pickup the mantle and post their results using their fridge. If you do, please place a glass of water in your fridge at on the shelf where your starter is stored. Take the water temp after 12 hr or so and post that with your findings.
Room Temperature Starters - Room Temperature Starters - Room Temperature Starters -
The starter below was kept on the counter at room temperature (71F). It was mixed 1:3:5 using 80% AP and 20% Whole Rye.
Danny