Shields Have special Rulings that circumvent Shield Text.
1. Shields Always prevent damage from Physical Sources Only unless Stated Otherwise and do so by reducing any positive Atk by the damage reduction to a minimum of 0. In the case of an Evasion shield, the value is simply set to 0 if the Trigger chance is rolled.
2. Creatures that have Atk less than or equal to the damage prevention value of a Shield do not trigger a Shield Response. This Includes 0 and negative attack creatures.
If there are any other stuffups on card text, note them in the Bug section.