Can titles be both keyword-oriented AND clever at the same time?
Answer: Wrong question.
Of course it can't hurt to have your keywords from your story reflected in the headline, it helps keep Google from having a snit, and clever is fine if you can do it, but both of them treat the post as an entity in its own right, something separate from anything else on the net, and that is absolutely the last thing I want.
In a Networked World, the most important thing is to tie yourself to as many other nodes in the net as possible, to see what you are writing as not original and outstanding but as part of the overall discourse of the subject that you are participating in.
I try to split out posts that I'm starting fresh with no, or little, specific source material from those where I'm picking up on something else like a blog post or a news story. In the original posts there's room to be a bit lighter because, lets face it, most of the people who read it are going to be your regulars who should come to recognise your voice from reading the content. On the other hand, you still want to be sure that it contains enough clarity to indicate the content, in the end, sacrifice clever for clear.
But when I'm using someone else's material as a starting point, then there is sense in being as common as muck. I try to use either the headline of the original story or quote some part of it. The reason is simple, since the original headline probably contains the keywords for the story, and since those keywords will become tags in Technorati or Google, you want to hook into them as tightly as possible.
Because if I'm attracted by the headline, others will be too, then they'll search for those words, maybe in Google news to see who else had ripped and read from AP or Reuters or Larry Lessig, and I want to be there in the results for as close to those combinations as possible.