The things you listed are considered when formulating payroll. TM experience, turnover and important metrics are included as well. Ultimately, it's up to the DTL where the hours go. If a DTL has a poor performing store, I wouldn't be surprised if that store received additional help, as far as payroll. If a store is performing well, I wouldn't be surprised if a DTL trimmed that store's payroll and redistributed it throughout the rest of the district.
The key is under payroll. You can achieve golden contribution if you are 1 hour under payroll or 1000 hours under payroll. However, as multiple other have already pointed out in this thread, the more hours you save, the more negative consequences arise.
Again, STLs are not rewarded for saving a lot of payroll. Sure, every store needs to be fiscally accountable and not spend more payroll than you are allocated, but saving a ton of hours is not beneficial to anyone, including STLs. Ask
@Rock Lobster when the last time they or their STL received any sort of benefit from repeatedly saving 30% payroll.
As long as we are on the topic of payroll, I might as well point ot these 2 recent changes: stores can no longer lose payroll by missing sales forecasts, and flex hours gained during the first half of the month are not all lost if your sales tank during the second half of the month. (Flex hours are hours of payroll gained by doing more sales vs forecast).