I found your 'seemingly simple questions' very interesting (I hadn't really noticed Use for identification
until I saw your question). However, listening to the Stack Exchange podcasts, one of the main things that they highlight is that they want the answers on Stack Exchange to be the best answer on the internet (for that question).
If you found the answer very easily and well explained elsewhere, then I would suggest that it is easy for someone else with the same question to find the answer there too. Therefore, I would suggest that these questions do not need to be asked on the Tridion Stack Exchange site.
However, if you had to do some investigation across multiple locations, or some investigation of your own, then this probably would be a good question to ask and then self-answer. I would be reluctant to ask questions here as a pop quiz. If you know the answer, or suspect that someone could enhance/clarify it, then I would recommend asking and self-answering.
It is often very useful to read "IS this approach sound?" type questions, as it can help everyone to improve method/patterns for doing common tasks. I would say that these too are acceptable as long as they fully define the scope of the problem, fully document any investigation/findings that you have already done and can have a definitive answer.
The Help section says that we should try to avoid chatty, open-ended questions or ones that have no right answer (e.g. "What is your favourite ____ ?"). However, I think that this leaves a gap in the community now that the old forums are read only. Individual blog post are very interesting, but do not really attract much conversation, and they are spread across multiple sites. I am not proposing that we resurrect the forums, but I think that somewhere for any 'chatty' questions may useful to ensure that the Tridion Stack Exchange site stays clean. All ideas are welcomed!