[protomyth]

Most advise is dangerous if taken way too literally. People just need to understand than they are conveying a message with their face, posture, and hand movements. Don't communicate a bad one or worse, one you don't intend to communicate. Managers sometimes have to deliver bad news that they might not be on board with. Don't make a bad situation worse by saying one thing and having your face betray you. I remember a training video I was forced to watch that had an actor say the exact same words three times with totally different meanings because of the signal their non-verbal communication was making.

Being stoic all the time communicates quite a lot and not in a good way.