the metadata that gets written to the XMP files do not include the full history of edits that were made on the photo
Very true, I didn’t think to mention that aspect of it… Thanks for bringing that to my attention!
However, I’d still far rather have all my edits without history, than to lose my edits all together! 🙂 I don’t do much with flags/ratings etc, so I didn’t know about that issue. It’s good to know though, so that you’re prepared!
BTW I do highly recommend that you zip/compress your Lightroom Catalog after backup. The catalog backup by itself can be quite large, but it is highly compressible. For example, my current catalog backup is 127 MB, but by compressing into .zip format, I brought down to a mere 9 MB, which is only 7.087% of the original! If you back up frequently, that can add up to some huge savings in the long run!