Is "Ben's Best Guess Table" too conservative for some residential pools? I've seen more than a few people here claim to keep their chlorine at levels significantly lower than the Best Guess Table calls for for a given level of CYA with good results (no algae, no known cases of pathogen transmission through the pool water, etc.). Are they just lucky or might it be safe to keep lower levels of chlorine in certain circumstances? Is Ben's table heavily based on his experience with commercial pools? Is there a safety factor built-in to the table?

Without knowing and controlling for the myriad variables (bather load, accident-prone kid load, leaves and other vegetable matter, sunlight, etc.) that affect chlorine consumption, there would obviously be a good bit of guesswork involved in refining the table at all. However, given all the concern about safe chlorine levels it may be something worthy of further discussion.

I'm not advocating that anyone run lower levels of chlorine than Ben recommends; I'm just suggesting that based on some (admittedly sketchy) anecdotal evidence, some further discussion/inquiry might by in order. Short of that, should the table be treated as more of a starting point or guideline than an absolute? That may even have been Ben's original intent but almost everyone here (me included) now treats it as Gospel instead of as a guide.

(Just some food for thought and discussion; I'm not looking to start an argument.)