Realize yer talking about "shaving soap", but.. Just a quick side, that "regular bar soap" is Also a good 'deep-stacker' -
If you 'stack wisely', ie: "Zote" is really a solid '2 fer 1', because it's both great for Laundry (whole-bar, and/or 'cheese-gratered-up' + Borax, etc),
and Skin.. Toss back plenty of Fels-Naptha, as well, for tougher-stains / dish-soap, etc..
But Not long-term shaving, oww..
I'm sure I must be 'preaching to the Choir', here, tho..
We also stack/pack lots of 'Olive Oil soap', as it's Great for dry-tendency skin, full-body, +
Shaving, and rinses clean with Cold water, as well as Hot..
.03
jd