The discussion of the mysterious double-solution topic brought up a question that's come up before, which is what to do when there are multiple good answers:
As I understand it, one of this community's goals is not to be strictly a "there is one right answer" Q&A site, but also to support more free-ranging discussion and allow people to support each other even if a "right" answer doesn't exist. I have definitely seen cases where there are lots of great answers, because there's often more than one way to do it, and this community is lucky to have lots of creative members! 
So rather than admonishing people to only choose one solution, what if we offered more guidance about what to do when they wanted to recognize multiple helpful answers?
Here's one idea: to handle multiple valid or helpful answers or suggestions, how about posting a new reply quoting parts of the best answers, then marking that as the solution? By quoting helpers, the OP is still giving them credit, and others who come along later will be able to easily find what they felt were the most helpful posts. And that's the core point of marking solutions as far as this community is concerned!