You make it sound easy (and in some ways it is..) its like floating.. alive human bodies do want to float.. but if we are tense, or fight, or just try, we can easily slip under the water. we shouldn't have to learn how to float. but most of do!

learning to keep with in ourselves, and not take on other anger is hard (especially if you are emotionally involved..) we tend, to mirror the ones we love (watch a couple in love, they will almost always mirror each other, how they sit, where their hand are.. sometimes even clothes!)

it is a hard trick, to be able to be emotionally involved, and not to mirror.. to stay with in our selves.. especially where emotions are involved!

good customer service skills require you to remain in your self, no matter how angry (or annoying!) the customer is..

and there are people who are adept at "Passing off emotions"
(being angry is requires more effort than being calm... if they teach you to get angry for them, they can save their energy for other stuff..) if you let your self be manipulated that way, you spend all your time and energy being mad!--

classic is a kid, who tells her mother how horrid the her husband is.. the mother get angry, and hostile to son in law, the daughter defends hubby, and get closer to him.. and at the same time defends mommy.-- "problem" is always the mother in law.. reality is its a three way triangle. daughter is using Mother to get angry at husband..

an other classic, parents are fighting.. it scares a kid. Kid does something stupid (totals car) Parent are now in agreement--Kid is stupid! (kid is happy, parent are no longer fighting.. Kid would rather be labeled stupid, than listen to parent fight. )