Do's and Don'ts in public questioning

From How to Ask a Question by Peter Wood, a good essay on what to consider when asking a public question. The main point, though he doesn't put it this way, is that a dialogue is a form of conversation and therefore one's primary consideration ought to be how to keep the conversation constructive and flowing. I think Wood is right that far too often the mindset of the questioners is instead focused on how to extract something from the opposition or how to make oneself look better. Here is my list of pointers based on Wood's essay.

Do
Be succinct
Be civil
Be interesting
Help the person being questioned to clarify their point
Ask
Build on the existing dialogue
Serve as a catalyst for the responder to offer insight
Stick to a single point
Maintain contextual pertinence
Lead with Who, Where, What, Why, When or How
Go straight to the question

Don't
Use the question as a platform to demonstrate your own superiority
Scold
Pursue tangents, minutiae or the irrelevant
Declare
Focus on yourself or your point
Make a speech
Seek clarification of or offer additional factual details
Seek to nail down an evasive answer
Don't repeat a question already answered
Lead with your biography
Attack
Offer yourself as a representative of some group