Let me add to those rule of thumbs.
-Use injector scale to correct across the board errors. (OFFSET aka ZERO)
-Use injector latency to correct errors that change linearly as the injector pulse width changes. (SLOPE). Need to watch battery voltage on this one.
-Use MAF table to fine tune random minor errors.
This assumes stock or injector changes only and no vacuum/boost leaks. If you change the intake then you'd make most of your changes in the MAF table.