Retail Replenishment - How tuned in are you?

I spent about 9 hours yesterday analyzing sales, order and forecast data for Walmart, Home Depot and Lowe's vendors, and I am somewhat surprised by my observations.  It's pretty clear that there are some min/max rules in place, as I can see patterns to the order quantities based on the OH inventory and the order case pack quantities.  However, what surprises me is that I also see a large number of what I would guess are "manual overrides." That is UPC/stores which clearly need inventory and fall under the minimum OH of other stores, but which do not have an open order, and UPC/stores that are clearly overstocked (e.g. high WOS), and yet have an open order.  It makes sense that there would be automated replenishment rules in place and then some lead-way for the buyer/replenishment manager to make judgment calls, so that leads me to my question....

What do you know about your key retail customer's replenishment rules?

• Simple min/max ordering?
• Based on OTB dollars?
• WOS trigger?
• At what level is demand calculated?  e.g. Category/Region, Category/State, Sub-category/State
• Under what situations will the buyer do a manual override?