Genius Advice

A couple of Apple ``geniuses'' (who looked at my dead MacBook Pro) advised using Migration Assistant or copying from backup directories only for personal data. Their advice was to reinstall all applications from scratch. Instead, I decided to use rsync⁵ to copy everything from backup (as described below) because

1. my time is limited,
2. I did this successfully for everything but Xcode before (§5.6), and
3. my dead system was quite up to date, so anything I whack on the new machine should be an upgrade of it.

I did worry, however, that upgrading only some system files (e.g., in /Library), before running Software Update to update the whole system, might confuse the Software Update enough to abort it (things like that happen all the time using the Windows installer/uninstaller--you generally cannot uninstall anything that is already partially uninstalled, for example), but it seemed to go fine. Chalk up another point for the Apple software engineers who wrote the Software Update code! Of course any software update or uninstall should be able to forge ahead no matter what, perhaps with options.