How is it is supposed to work: your emotions are a response to your situation and surroundings. It is OK to feel the emotion. Now take that emotion and use your logical brain to decide which parts of the emotion fit the facts of the situation and which do not and why, and how you're going to respond to said emotions (which is what tweet said, and what therapists say)
How people seem to interpret it: any emotional reaction is perfectly fine and I am not responsible for what I do out of emotion.
The "How it is supposed to work" part is really great, took me long enough and a therapist to figure that.