BTW, I used a combination of revision IDs and timestamps, because you told me the revision IDs can get out of order through deleting/undeleting revisions, and I wanted them in correct order no matter what.
You should use IDs (and never timestamps) for purposes of uniquely identifying a row, not for sorting. You should use timestamps (and never IDs) for sorting purposes, and never for unique identification. You shouldn't ever need to use a combination of both for a single purpose.
Timwi