[ryandrake]

Thanks! After hours of downvoting, yours is the first response to actually answer my question with a thoughtful, actionable way to address the feedback about Sten in OP's scenario. Given the number of, shall we say, socially awkward people in tech, it's entirely believable that Sten had no idea that silently watching someone work could make them uncomfortable. We've all worked with people who were a little "off" socially but without ill intent. Social/etiquette rules are messy and inconsistent, and they don't come naturally to everyone. I know I'd have a hard time articulating feedback like: This kind of looking is good, this kind is bad. You can make eye contact with people at work, but don't hold it more than N seconds. You can stand near people but no less than N meters, and not directly facing them. You don't often see that level of detail in HR training literature.

Maybe in OP's example there actually was ill intent, and maybe there wasn't. Hard to tell given the text. I think it's a marvelous skill to be able to delicately address someone else's "creepy behavior" when you aren't sure of the intent behind it.