I admit, the title was meant to be annoying and to get your attention. Did it work?
These following links just show performance data (salt efficiency settings, water used for regeneration and regeneration time) from different manufacturers.
The point being, there are many softener systems with over a 4,500 grains/lb of salt efficiency. I have even seen a few above the 5,000 grains/lb. It is understood that in theory the maximum salt efficiency is 6,000 grains/lb.
As per; http://www.wcponline.com/pdf/WaterMatters0306.pdf
Figure 3: NSF/ANSI 44 efficiency requirements (DIR softeners only)
Parameter Efficiency requirement
Salt efficiency At least 3,350 grains of capacity per pound of regenerant salt
Water efficiency At least 1,000 grains of capacity per 5 gallons of regeneration water
The experts here seem to recommend a 6lb-8lb salt does per cuft. Or 3,333 grains/lb to 3,000 grains/lb.
Why are you experts recommending something that would be breaking the law in California with it's 4,000 grains/lb ? Do you also see those short regeneration times (17 minutes on one of them).
Where am I mistaken? I also understand the hardness bleed-through issue. Has anyone done a double bind study on this? At what level of harness ppm are people aware of it?
*Disclaimer* I don't really know crap about water softeners.