It's the old bimodal distribution effect and trying to draw a linear correlation between them, or that meme with the two sides of the bell curve. At some level

It's the old bimodal distribution effect and trying to draw a linear correlation between them, or that meme with the two sides of the bell curve. At some level, swearing is an indicator of emotional immaturity and a preponderance of subjectivity. At another level, not swearing is repression, oppresion and a denial of reality and any investment in the project. So what we want to see in the best projects are the programmers who are emotionally invested yet also objective enough to swear at the real situations around themselves and not repress themselves, but who aren't so emotionally immature as to swear because it's cool/edgy :)