I think there are kind of 2 different things being discussed here.
From what I understand, you have to have a master contract to start out. So, as a new member you have to purchase the minimum buy-in relevant to whatever resort you are purchasing in 1 undivided amount. (So "no" to the 3 25's as a new member).
Link to minimums (that may or may not be enforced) here....
https://dvcnews.com/index.php/dvc-program/financial/pricing-a-promotions
The only way I know of to start with a 25 point master contract is to buy it resale.
What some people I think are discussing is if you ADD-ON 3 25's direct, does it get you full benefits and it seems most of us believe the answer to that is "yes".
For you, I assume they were selling you CCV, which has a 75 or 100 (depending on who you talk to) minimum for new members. So to buy all at once they won't let you divide the initital 75 but you could buy the 75 or 100 initially and add on 50 at a time. Now, maybe if you were saying you wanted all 3 contracts to be completely equal, they were saying that buying 3 75's was the only way. - which would be true.
So, the only way I can see one could ONLY hold 3 - 25 direct contracts is if you already had a "master contract" (either direct or resale), added on 3 25s direct and then sold your master.