The nanny systems on the Compass and a few of the other newer vehicles are actually pretty good. They are sensitive to detect wheel slippage in a matter of a few degrees of tire rotation. The system also knows all of your inputs including how far the steering wheel is turned to try to determine where you are trying to go and keep you moving in that direction. It feels to be like some gyros are a play here as well as you can feel the system kick in when there has been no tire slippage at all. However yes it is still a mostly reactive system and a good driver may never see these systems in full action. In the case of the Compass the system stays pretty tight even when muted by partly turning it off. But given the driving skills of most drivers these day it is most likely a good thing in a higher CG SUV.I still have my doubts about how sensitive the ESC is. Having driven a FWD Patriot in snow for 10 years I learned early on that a wheel must have significant slippage before the ETC kicked in. I am presuming the ETC and ESC are working with the same data. It is measuring the difference in wheel speeds and it must take into account that someone may be turning sharply so it simply can't engage on every tight turn. So really, the ESC is only there in a situation one should avoid in the first place. Relying on ESC is like relying on airbags or seatbelts -- if you need them you got yourself into a situation you shouldn't have.
I have driven the Snake in our Compass many times both with the system partly and fully engaged. The only difference is the Compass feels lighter and more fun with the system muted and it loses that hard pull to the inside of the curves the torque feed back to the steering wheel is muted the system lets you have some drift before engaging the brakes on the inside track. However hit a curve faster than it likes the nanny will kick in and you feel it reigning you back in. With the system full on the Compass almost feels so stiff it at times feels like it could break in half going around a hair pin switchback. Seriously if it were not for the lack of binding it could be so stiff it felt like all 4 wheels were hard connected to each other without any means to allow for different wheel speeds. I have driven Subarus that were not this tight in sharp curves.
Truly though muting the ESC is pretty much the same as switching to a sport mode on the ESC in other vehicles it just moves the nanny to the back seat and out of your face!
As for seatbelts and airbags there are just too many variables that can happen where even the best of drivers can end up using them. We simply can't account for everything and given how stupid people are getting behind the wheel anything becomes possible at any moment.