I'm unclear the reason for downvotes. Perhaps some think it's a bad idea in the first place, and if that is explained in an answer all is good but why the need to downvote?
In my experience here over the past years, people primarily downvote and upvote basically based off:
Do I like this question?
Not anything other than that.
So if you suggest a "bad idea" or an unpopular idea, you'll get downvotes, regardless of question merit.
Conversely, questions which programmers can empathize with generally get upvoted.
Likewise, often answers are voted on "yeah, I agree!" vs "yes, this is a good answer" criteria.
Some of both, I think.
A good question that's asked badly can attract downvotes, but you're asking about the reverse, a well-asked question that's about something that strikes the reader as a really stupid idea. For that, I fall back on the guidance given in the mouse-over text on the buttons: is this question useful?
If a question is about something that's a bad idea but comes up a lot, I'll probably upvote the question and look for (or write) a "don't do that; here's why" answer. Hypothetical example: "How can I get my employees to work long hours every week without increasing their compensation?"
But if a question just has "bad idea" written all over it, something that I can't imagine being a common or serious problem in the workplace, I'm likely to downvote that no matter how well it's written. Hypothetical example: "My company doesn't pay me enough; how can I embezzle money from the corporate account without being caught?"
The question you linked to is somewhere between these. IMO it's not very well-asked, and it seems to be looking for help with something that's a bad idea (convincing his boss to waive his responsibilities), and it's not something that strikes me as a real problem to be solved. As one of the answers put it, "what's the big deal?" (I'm not accusing the asker of insincerity; I just think that if he's not actually trying to get his boss to sign without reading, then it's kind of a trivial question, boiling down to "how do I tell my boss I've already read this?".)
Nobody is happy answering questions of the type "What can I do to push this really bad idea through ? Help me" That kind of question leaves a bad taste in the mouth. I'd like to think that we are about helping askers exercise sound judgement and solid professional behavior, which will help them and other readers navigate their career in a sound, solid way. You are not only about the answers you give but about the questions you ask.
Form in the form of a well constructed question matters, but content matters at least the much. People go to this site for cpntent not necessarily to exclusively marvel at how well a question is constructed. Content in the form of solid, actionable answers to specific questions that are scalable to a number of people is what keeps the readers coming back.