History, Undo, People, and Keyword Tagging

Is there any way to see the history of keyword tags (add, remove, change) on a given image or set of images?

One of the things I love about LR is the non-destructive history and the ability to see in what order changes were made and to roll back changes...  However it appears that ONLY changes made in develop are actually tracked in the history.

When applying keyword tags to photos, regardless of weather you are pushing the metadata to the file or just keeping it in the LR database, the history for a given photo is not updated.  While I still have LR open I can press undo and it will revert the keyword, however since it does not show up in the history I really have no way to see when the keyword was added or to undo unless I catch a mistake right away.

Keywords are not the only thing that is impacted.  I am unable to find history of ANY of the metadata changes, additions, deletions, for any of my photos.

I know this may not seem like a big problem for most, so please don't reply asking me I would need or want to see this in the history if it is not changing the visual nature of a photo.  For me the integrity of the metadata is critical.

The latest problem I have encountered is when dealing with a very large catalog and tagging people.  Once in a while I find several thousand faces that I had previously tagged as one person are now tagged with another person.  I don't know if this is a bug or if it is something I am doing.  I have done everything I can think of to prevent it from happening but it still happens. 

- I slow down

- I tag fewer images

- I only use shift-click to select a range and never ctrl-click

- I only use ctrl-click on individual images and never shift-click a range

- I verify that I have nothing else selected before selecting multiple photos to update.

The only time I have not experienced this issue is when adding keyword tags to an individual photo.  I never notice it when it happens, though I am constantly watching for anything that would indicate a mistake or unintended tag change.

Since I don't know when the error occured I am hesitant to keep hitting undo and hoping that the problem gets resolved and then having to figure out what else was undone.

This is why I need metadata or at least lightroom DB history.

Any help would be appreciated.