Currently the parent product (Click into a product and view the summary) is treated differently than the variants. This is good however it is frustrating when a merchant is managing their inventory
Scenario 1: when a tag is entered on a single variant product it should be automatically added to the "variant" as well (even if it is a single variant product the system automatically generates a variant for the product).
Scenario 2: when a tag is entered on a multi variant, provide a check box to apply to all variants, it should be selected as default and next to or below the tag entry field. This will allow the user to enter the tag on the parent and automatically apply it to all of the variants without having to change them manually.