no
100% = 100/100
50% = 50/100
100% - 50% - 50% is 0% = 0/100
That is what additive means.
This is multiplicative: 1 * 0.5 * 0.5 = 0.25 = 25%
So, total damage modified on crusher is multiplicative, not additive - which I was told that ALL “total damage modified by” are supposed to work as