Yes, negative answers are good, often users are unsure if some feature exists for their workflow. And if there is no way to accomplish the tasks its best to say so, And possibly suggest workarounds if they exist.
It's useful to know the limitation of technologies you use as well as the features.
In my own experience asking questions, I've noticed people ...
The "needs work" and similar judgments come from the Area51 stats.
We've pretty much always had a steady supply of questions which aren't easily answered, perhaps due to relative obscurity, or lack of OP responsiveness, other reasons.
These occasionally get a great answer, but most of the time they just join the pile and sit there. This ...