I've personally always disliked Sanity systems, even though I've incorporated some into certain systems I've written. I understand how in a CoC or similar system game they would be critical, which includes most horror settings. I prefer to let the players feel like they are the heroes they want to play instead of the typical person from our world. Some prefer this and there is nothing wrong with that, I just like to play settings that are more heroic.
All this to say that however Chaosium works the new Sanity system, won't affect me or my group much. I wouldn't get too worked up about it as far as Sanity in a realistic sense goes, anything can make someone breakdown, not just a comparison to a "magical" ability.