This feature allows to select for which countries a “Recommended Carrier” notification will be shown under DHL shipping option in Checkout. You can select countries on this setting page in Magento Admin under “DHL Worldwide Express” tab in “Show as Recommended for Countries” field.
[alert]This shipping method is actually not used to anymore to show DHL shipping options in Checkout, but it’s configuration screen is used to allow selecting countries for this feature.[/alert]