You may want to verify with DVC the definition they will use for "member". It may mean each name on the contract, as Dean suggests, but it may also have another meaning. Right now DVC claims something like 86,000 "members" and insist that number represents unique memberships and not the number of contracts owned or the number of names on the contracts.
The number of passes allowed could be eight per unique member. I have been told that my wife and I count as 1 unique member within the collective 86,000+ members of DVC. Even though we, together, own several contracts, we are counted as 1 of the total number of DVC members.
Before going to the expense and trouble of adding names to a deed just to get the AP discount, it might be wise to make sure that action will accomplish what you're really after.
If you get a definitive answer, please report back!