It is a good thing to do in respects to SEO. The situation I am thinking about is if it violates best practices in respect to framing. Questions are upvoted when they are asked well and represent an good piece of knowledge to be gained. I myself (and likely others) visit stack exchange often through search engine links and would feel responsible for the keywords that would be picked up.
Please excuse the contrived example. If I asked the question:
What is the quickest way to destroy a friends linux system?
Keywords: quick, destroy, system
Assuming it would be upvoted since it asks a specific question and technically there is knowledge that would be gained.
I would likely want to delete and rewrite:
What methods do I have to protect against to prevent a quick destruction of my system?
Keywords: methods, protect, destruction, system
While the answer would be the same, I think the traffic coming to the site would be of higher value. I should note this isn't about keeping people out. It would be better questioning to funnel traffic into the site with higher accuracy. I would prefer a stack exchange answer to most things and I have already found that certain positive words lead me to this site quicker.