I used the DVC as a conduit simply to generate the gift cards. We had purchased gift cards from Target. Rather than using them to pay WDW directly, I input them into my DVC account and then paid off my package from there.
$950 cash to Target gives me $1,000 of gift cards that goes through my DVC to generate another $20 gift card. So $950 to Target = $1,020 worth of Disney. OTOH, $950 directly to Disney only buys me $950 worth of Disney.
Caveat: The DVC must be open at least 120 days at the time it is used to pay WDW in order to earn the gift cards.