A Calming Presence
There's a lot of metaphors for this type of personality: "keeps their cool," "staying cool under pressure," etc., but it all represents the same thing: the ability that some people have to stay calm and even influence others when things get a little hectic.
I've had my fair share of hairy hosting situations, and I can tell you in all honesty that the #1 reason I stick with certain hosting companies is due to the ability of their customer support team to keep me from pulling my hair out.
The best customer service reps know that they cannot let a heated customer force them to lose their cool; in fact it is their job to try to be the "rock" for a customer who thinks the world is falling down due to their current problem.