[jnsaff2]

I guess this is about predictability.

I know what (and where) the problematic spots are for the lane-keeping, so I use it in situations where the benefit is large and the risk is manageable.

There are many places where I won't switch it on and just drive myself.

Also 99% vs 1% depends on how you look at it. The main road I drive is about 200km long, in one direction it does not have any problematic spots. In the other it has 2 lets say 10 meter spots. By distance it's 0.01% problematic. It's not like Desert Bus where it tries to get you all the time.