If you are unsure because the OP was ambiguous, then post with caveats. If you're not sure about it from a technical standpoint, the don't post. As others mentioned, if the post goes unanswered for a day or so, then go ahead and post with caveats/disclaimers.

The worst possible thing you can do is post both technically accurate answers to simpler questions (or on subjects you are much more familiar with) and ones you have little clue about. Because the Monks that have begun to rely on your correct answers will believe the ones that you have no clue about as well.