I'd like to propose that all edits performed on a question are visible in the review history. Specifically, I'm asking that the five minute grace period goes away from the perspective of the revision history.
I still think a five minute window needs to exist in terms of the community-wiki edit count. I don't want people shying away from small corrections and typos in their own questions, for fear of turning their question into a CW.
This has several benefits:
It can help reduce confusion when answers/comments are rendered obsolete by changes to the question within the first five minutes.
It can provide valuable insight into the history of the question; it can be helpful to see how the OP is responding to comments.
It may help users understand badly worded questions – often these are caused by multiple edits without much thought to the overall structure.
It can make it easier to see when a 2k+ user is mid-way through an edit spree. This might help avoid mid-air edit collisions.
There are potentially some down-sides, of course:
Noisy revision histories. Personally I think the benefits outweigh this down-side. It's not that bad to see some additional revisions.
Embarrassment. You can't hide your spelling/grammar mistakes. Oh well!
Performance - storing additional revision data in the database will impact performance. Is this significant and can this be managed?
I think complete transparency is a good thing on this site and matches well to the values of openness and ownership of content.
(Inspired, in part, by Make first draft of a new answer part of the permanent revision history)