How much Dodge bypass do purple named creatures get?

[Carpone]

Spell Resistance is overcome by Spell Penetration.
Armor Class is overcome by Attack.
Fortification is overcome by Armor Piercing.
Dodge is overcome by Dodge bypass. [Really need a name for this mechanic.]

The tech already exists in Shadowdancer (Grim Precision) to bypass enemy Dodge rating. So how much of that Dodge bypass is going to be added to purple named monsters? Not exactly something that players can test easily.