From The Vault
Domesticated is a Fallout Tactics Trait, available only to deathclaws.
You have undergone extensive house training and have developed higher than normal Intelligence. However you do less unarmed damage.
This is not a trait you will want for a deathclaw, as the only thing a deathclaw is good at is unarmed combat, and obviously with this trait its combat damage will be much reduced. That's why Mother is not a very good recruit, regardless of her impressive array of stats, traits and perks.