This topic comes up from time to time with the common theme being that harder soaps last longer.
I don't think that's necessarily the case. Consider this:
There is a minimum required amount of soap to create enough lather for your shave. We can look at that amount in terms of weight (let's assume it's 1g for the sake of discussion). 1g of soap is 1g of soap, regardless of the soap's hardness. So while some soaps may require more per lather, it can be attributed mostly to the soap's recipe instead of its density. Admittedly, it's easier to use more of a soft soap than it is a hard soap and I'm sure that's helped perpetuate the idea.
But what about triple milled?
In the early days of soap making, the purity of the ingredients and potency of the lye was inconsistent and thus, difficult to measure. Soap was created much like an artisan would create it today, but due to those inconsistencies it also had to be boiled to remove said impurities and salted to precipitate out the excess lye. The result was a soap with way too much water in it. The need to remove that additional water lead to the triple milling technique.
Today, its necessity stems from the outsourcing of soap as "soap noodles" (a soap base that looks a lot like noodles). Companies will buy those bases and add their own botanicals, cosmetics, fragrances, etc. to them. Any idea what the easiest way to do that is? Triple milling!
So, while the finished result of a triple milled soap makes it easier to handle and package, neither are realized advantages in terms of a soap's general performance as it relates to shaving. As it relates to artisans, soaps are generally created with the minimum amount of water necessary to mix the lye; a lot of which is then evaporated out during the hot process cook. And since the soap is completely created in house, botanicals, cosmetics, fragrances, etc. are introduced into the soap before it's hardened, making the blending process both efficient and effective.
TL;DR:
I don't think that's necessarily the case. Consider this:
There is a minimum required amount of soap to create enough lather for your shave. We can look at that amount in terms of weight (let's assume it's 1g for the sake of discussion). 1g of soap is 1g of soap, regardless of the soap's hardness. So while some soaps may require more per lather, it can be attributed mostly to the soap's recipe instead of its density. Admittedly, it's easier to use more of a soft soap than it is a hard soap and I'm sure that's helped perpetuate the idea.
But what about triple milled?
In the early days of soap making, the purity of the ingredients and potency of the lye was inconsistent and thus, difficult to measure. Soap was created much like an artisan would create it today, but due to those inconsistencies it also had to be boiled to remove said impurities and salted to precipitate out the excess lye. The result was a soap with way too much water in it. The need to remove that additional water lead to the triple milling technique.
Today, its necessity stems from the outsourcing of soap as "soap noodles" (a soap base that looks a lot like noodles). Companies will buy those bases and add their own botanicals, cosmetics, fragrances, etc. to them. Any idea what the easiest way to do that is? Triple milling!
So, while the finished result of a triple milled soap makes it easier to handle and package, neither are realized advantages in terms of a soap's general performance as it relates to shaving. As it relates to artisans, soaps are generally created with the minimum amount of water necessary to mix the lye; a lot of which is then evaporated out during the hot process cook. And since the soap is completely created in house, botanicals, cosmetics, fragrances, etc. are introduced into the soap before it's hardened, making the blending process both efficient and effective.
TL;DR:
- 1g of soap is 1g of soap
- Triple Milling is the result of necessity, not advantage