I see your point. I agree that in a chronological thread model, heavy editing is not warranted.

That raises two follow-up questions:

1. How should light editing be handled?
2. If a question would require heavy editing, is it appropriate to repeat the entire question in heavily edited form?

I would propose the following answers:

1. The original poster should be contacted by private message, pointing out the errors and how to correct them. The original poster should not take offense.
2. Yes.

The question that remains is how to distinguish these cases.