Simple, CPM-3v is less likely to chip when it's in a thin blade stock compared to something like S90v, depending on what you're cutting. Especially if you're cutting a pretty abrasive material full of particles like sand (think dirty rope), that superior toughness can handle coming into contact with those hard sand particles which might mean better edge retention compared to a brittle steel that'll microchip like crazy when it hits the sand in that rope (ie. the S90V and S110V's of the world). Also CPM-3v is slightly more stainless than Cru-Wear in addition to being tougher, edge retention isn't the end all be all of knives, otherwise all knives would be made of ceramic, obsidian, glass or similarly chippy, ultra high wear resistance materials.
Now for my own little aside- There's this trend I see in the knife community that's kind of silly IMO. People make these big thick knives in super tough steels like CPM-3V and Cru-Wear and then these super thin slicey knives in something like S90V, when IMO it should be the other way around. A tough steel (ie. CPM-3v) can handle being ground super thin and slicey without horrendous amounts of micro chipping, whereas a steel prone to chipping like S90v might benefit from a thicker blade stock. A steel like 1095 that has a measured toughness less than many modern stainless steels (at higher HRC's nonetheless) has a reputation for being tough because everyone making knives in 1095 are making super thick knives. In theory, if we're going by Dr. Larrin's numbers, something like an Esee-5 in S-35vn would actually be stronger than an Esee-5 in it's standard 1095 assuming both steels are at the same hardness. So what's with this trope of making sharpened prybars in tough steel that if ground thin would hold an excellent edge with close to no micro chipping for 99% of knife related tasks and then making these super thin knives in steels that will microchip while cutting cardboard?
