First, let me say that I completely understand the idea of not posting full solutions, but instead "hints" (or outlines) to let the OP figure out the details by themselves. I tend to do that myself.
Now, I have seen quite a few times (maybe more frequently these past months, although I cannot say it for sure) supposed hints that were actually wrong. That is, either barely better than a comment suggesting a first step (and definitely not enough for the OP to figure out what to do after that); or, even worse, suggestions to go in a direction that would not work.
(The latter, I reckon, being a sign that the person answering is just there to harvest points quickly, and did not actually follow their own suggestion to see if it did go through).
Should there be an officially stated policy about these hints? (e.g., a mention like "only post such answers after checking that this indeed is a valid and fruitful approach to the question; and provides enough insight to continue the argument.")