I am well aware not to get involved in debating a topic unless I am quite knowledgable in said topic.
I don't think that means you have to just lurk. I think it just means you have to be careful in the approach you choose when posting. There is nothing wrong with asking honest questions to get something clarified if someone says something you don't understand.
There is also nothing wrong with saying what you think you already know or have heard somewhere. You just shouldn't be too dogmatic about it until you've gathered a bit more information.
Heck, I post stuff all the time when I'm only partially informed on the topic.
I think there would be a very much smaller number of posts if only those who really knew something about the topic posted. LOL
You may have seen some somewhat annoyed reactions to postings by those who display (proudly even) ignorance and dogmatism at the same time.