The "wo that is in marriage," of which the Wife of Bath purposes to speak, comes about mainly because of a woman's desire for "maistrye," or complete control over her husband, possessions, and self. At least so goes the thinking in the Wife of Bath's Prologue. The Wife's method of gaining power often takes the form of capturing the moral high ground: she accuses her husbands of saying insulting things to her, or of cheating, in order to make them feel so guilty they give in to her desires. The Wife also emphasizes the importance of gaining control over the property in a relationship, although it's sometimes unclear whether gaining power results from gaining control of property, or vice versa.
The Wife shows an awareness of rhetorical as well as material power. According to her, (male) clerks have been able to insult women in writing for centuries because they've always had control of the pen; had women that power, they'd be able to respond and also to paint men in an unfavorable light. With this idea, the Wife's of Bath's Prologue gains a new awareness of itself as rhetorically powerful, a power upon which it capitalizes to both confirm and trouble antifeminist rhetoric.
The Wife of Bath's Prologue portrays most of the "wo in mariage" as a result of power struggles within the relationship.
The Wife of Bath employs control of property as a tool to gain power in a relationship.
The Wife of Bath uses her power in a relationship to gain control of property.