Yes and no. For add ons or even larger new contracts that you buy from DVC, they will be added to the master contract if they are the same EXACT registration. Same for resale purchase for those that are already a member in theory. Apparently DVC has missed a few not realizing one adding on resale was indeed a member. I'm told they will not go back and fix it if that "mistake" does happen. If the registration is different AT ALL, it must be a totally separate contract no matter how small or large. DVC will not sell retail for less than 150 points unless the registration is the same. The only semi exception I'm aware of was where someone bought 150 points but in two 75 pt contracts where DVC allowed them to register differently but they they became a separate contract.
Carol, while I may agree with your principle, it is not reality. In essentially every circumstance, DVC treats multiple contracts of a single owner just like two different people. So you can do anything you want between the two contracts that you and I could do. That includes transferring points just because I want to if the desire arises. Of course there is no question of remuneration in this transfer situation. Plus, as I stated earlier, DVC will allow transfer of banked or borrowed points on a case by case basis where appropriate otherwise. The problem DVC has with handling the conversion is one they will have to deal with. They would have no legal grounds for denying a transfer as you suggest they would. And if that means that my OKW Aug points became BW Dec points, that is up to DVC to remedy and thus far they've shown no inclination to do so. Frankly I wish they would.