(Edit: My experience includes Fortune 100 in consumer tech and finance)
In this scenario Stephen has been hired to write code/produce something, I'll go all-Marxist on this and say he was hired to produce plus-value. He was not hired to be sworn at, no matter how good or bad his code/work might be, and this is why swearing directly at people is unprofessional.
As an aside, I'm surprised at the people who say that swearing to other people's face is "manly" (or something of the sorts). In the part of the world that I live if you swear someone directly in the face you'd better be prepared for a physical fight or worse.
the point is it's taken in a certain spirit, and you can't force people who don't know you well, or don't share that sensibility, to partake of that spirit.
even if you personally prefer that style, it's hard to argue that it's effective from a practical perspective. for the large majority of people, the first example is far more likely to actually get you your desired result than 2nd.