Well it depends on the type of trolling and ****posting of course.
The main distinction being whether it is directly pissing off me. Of course. See, if it is pissing me off, then it is a bad type of ****posting. If it's not, it's good. It's simple!
No, but really there is a difference in how you present yourself. If you are obviously joking it is okay to let off some steam. Serious and angry people are the worst. People who are jokingly angry are okay. Seriously angry is scary. That's different.