The phrase "doth addition" can be replaced with numerous synonyms to convey the same meaning. Some of the synonyms could be "adds up to," "leads to an increase," "augments," "puts in more," or "further enhances." These words indicate that the given amount or factor is being increased or strengthened in some way. Other synonyms that can be used in place of "doth addition" include "introduces a component," "implies more," "accounts for more," and "builds upon." These synonyms are useful when trying to add emphasis or clarity to a statement that involves a numerical or quantitative reference. Ultimately, the right synonym will depend on the context in which the phrase is being used.