[NicoJuicy]

Well, I do agree that it's somewhat confronting, but it get's results pretty fast.

A lot of it really depends on how you say the: "If it's private, just say stfu and I will not ask anymore".

It can be funny and disarming. It means that you want to know what is going on and that they should have no problems with saying that they don't want to talk about it. It doesn't translate well to written text.

In a lot of cases, you don't need to follow-up anymore and they will talk from their own. They are aware that you won't ask anymore, without them going forward on initiating the talk.