Not sure if I missed something here. If you use 3lb per regeneration and it goes 24 days, wouldn't that be 9lb.? Are you saying that 3333gr/lb is a good setting? High efficiency? What would the settings be for a 4000 or 5000 gr/lb setting?
Yes, 9# (3*3) for the 24-days (at 8, 16, and day 24). The grains/pound is still correct, and it is still less salt for equivalent soft water. Gary mistyped, I think. The end result is while you could run the resin into the ground, i.e., down to zero capacity left after 24-days, it is not the most efficient way to do it. My guess, and this is an educated guess, is that similar to batteries, it's not the best way to get longevity with the resin to run it down to zero each cycle. If it started fully recharged, and you used say a third, and then recharged that third, if there were occasional guests, or heavy water usage, you'd probably handle that better as well rather than running it down fully.
There are multiple ways to program any system. Some work better than others. SOme make the system last longer. Some create operational problems (like salt bridges, or hard water bleed through). Some are more efficient in the use of expendables. You can handle the operation many ways. Some solutions work most of the time, some work all of the time. Some people can accept it not working all of the time. Lack of good flow from the well could have consequences, and some ignore that to their peril. A well that can change based on the water table needs possibly some extra margin. Each situation is different (but similar). Some want maximum efficiency. So, depending on your use patterns, your tolerance for occasional bleed through, and costs, your priorities may differ and your programming solution may vary. But, quibbling is counter productive. There are consequences to the decisions you make, and IF you are aware of them, and they are acceptable to you, then that's an okay solution. Many people don't care or want to understand what can be a complex situation, and want THE solution...well, there isn't ONE. Being educated as to the consequences of any desicion, to me, is worth the hassle of the investigation. To some, they just want an answer, no explanations, no what ifs, no consequences.
Might I suggest, when anyone provides an answer, they explain the consequences of that solution. I think Gary does this more than others, and because of that explanation and the fact that it can take a bit to explain, people then get confused. Personally, I generally don't have an issue with it, but then I've spent my whole life in highly technical things - missile and radar systems require attention to detail, and little tolerance for failure or problems. Most things in life don't have as severe consequences if they don't work properly. But, that is not to say that some things aren't complex.
We spend too much time bashing each other, and need to look at the solution and the benefits and consequences. More than one way will work. Point out where your solution works and why. Don't bash the others if they don't do it 'your' way. It's likely both can work, and you may not have considered the consequences, or they just aren't important to you since they don't happen often. Just like all of the codes we have for plumbing...most stuff will work fine if you take a shortcut. It only gives you grief under certain (unforseen, at least to you) circumstances...and if you don't do it to code, it could fail. Soft water isn't as critical, but some people have no tolerance for 'different'.
Let's try to keep this more civil. If you keep poking, eventually, that person will poke back. Keep it civil, and expain why and the consequences of that why, and then people can choose their tolerance level for themselves to the possible consequences.