Its actually extremely detrimental to wield dual bastard swords...they only have strikethrough when they're wielded two-handed, and as one-handed weapons they're worse than longsword or scimitar or battleaxe
If you're dual wielding, you probably should switch to dual Oathblades at 20, make one Sentient and start feeding it, and swap Bsword proficiency for Knight's Training if you can (or squeeze KT in somewhere else)