Wick is correct; the brine does help defeat the vapor jacket of water, which is the most severe of almost any quenchant and violent in its collapse; which is the reason for the inordinate amount of cracking and warping from water quenches. However, be it oil or water, much of it is less critical than you may think when you realize the vast majority of hardening issues are not with the quench but with the heating.
If folks saw the volume of e-mails that I have, above and beyond what I do on the various forums, they would realize I am not exaggerating when I say that I probably help a significant amount of the knifemaking population troubleshoot their heat treating, and I would say that about 75% of the time the signs point to heating mistakes more than quenching problems with hardening issues. This is especially so when water based quenchants are involved in blade sized cross sections because, in order for the ones that do survive to make it out of the water intact, maximum hardness is often avoided via incomplete austenitizing. Whether your as-quenched 1095 is only 62HRC from phases formed in the quench or from phases that were never fully dissolved, the end result is the same, the blade didn’t fully harden. Many knifemakers see a quenchant as a magic potion that does it all, but the quenchant doesn’t harden the blade- the knifemakers does, and the knifemaker needs to get the entire process right or no single part can fix the resulting problems.