It is here that abuse can often take place.
Skillful dominants are good at identifying emotional triggers.
It is very easy and even tempting to use these buttons destructively. To imply a sub is selfish for considering her needs is an attempt to imply guilt to avoid dealing with real issues. A lot is said within those 3 words. Safe is fairly clear. Sane means we don't do things to screw up with each others heads and we wont do things to each other that will land one of us in a psychiatric ward, ICU or the grave.