A free-shipping threshold changes what customers are willing to add. If your recommendation tiles run through that week, primary lift can look heroic for reasons that have little to do with the pair quality.
Our usual practice:
- Mark promo days explicitly in the extract.
- Produce a primary cut excluding those days.
- Produce a sensitivity cut that includes them with a clear label.
Buyers respect the honesty. Hiding the promo overlap is how charts lose the room. For a worked example in kitchenware, see the spring window story on our client stories page.