Now, is easy to delete all the revisions of the posts. All from a book or all from the installation.
But that is too complicate for the most of the situations as to delete all or none, give us litle flexibility and the most of the times we can not to delete the revisions, just in case.
In order to decrease the size of the database and to be more eficient, maybe we should have a system that will delete the revisions after a time. Like, all the revisions older than 6 months will be deleted. Maybe the administrator can choose the time frame.
Who need a old revisión? the most of the situations, nobody. We need a revisión for a short time frame, not long one. We can decrease 5-15% the database size.
I have the limitation of revisions to 5, good for a day by day work, but once the post is old, 5 revisions is too much and is hart to delete by hand one by one acros all the books/posts. Not efficient. I think.