Most revision control systems are broken, in that they only give you one chance to commit both the content and the accompanying message right first time at the same time. Even if he is capable enough to be the first person to realize that he made a mess, he cannot clean it up himself because ordinary developers don't generally have permission to suppress broken intermediate revisions and modify ill-considered log messages from previous check-ins, even if they haven't been seen let alone used by anyone else yet. If a little mess really bothers you, then how about doing something constructive to keep the system cleaner? Do people check in at the start of the day, or under pressure at the end of the day? How about upgrading the revision control workflow to include a template, checklist, "are you sure" confirmations, reviewing, and even some automated formatting and validation for the message and content?