That will work. If you and your partner can manage to split a meal, then you can split a meal at another restaurant. Do keep in mind that (1) Disney reserves the right to stop the practice of splitting meals at any time, without notice, and (2) they are already making changes to their offerings to make splitting of a meal less attractive of an option, reducing portion sizes, for example.
Generally, if you feel you need to "stretch" your credits, then perhaps the Dining Plan isn't a good enough value for you.