[a1369209993]

> Often X really is something possible-but-difficult

If "I'll need a research team and five years" is actually a valid answer to X (eg: X="How do I determine if a given jpeg image contains a bird?", at least... uh, five years ago), then it's a valid answer for the purposes of answering both X and Y. The problem is people giving incorrect/non-answers like "you shouldn't do that", and then pretending they answered the question because they also gave a (presumed for the sake of argument to be correct) answer to some different question, Y.