Sorry, I have to correct / clarify this statement. The OP owns a HGVC deed, and if they add a resale HGVC or HC deed, the points most certainly DO merge. Quite nicely, in fact. However, if they buy Diamond points / deed resale, that would not merge (not sure if that's what you were talking about, so giving you the benefit of the doubt).
This is very important, as salespeople will try and tell you that resale deeds cannot be merged into your account, saying that the only way to do that is to buy retail. Of course, they will say almost any lie to entice you to buy retail so they can get their fat commission check.
Kurt
I understood the discussion to be about the use of retail/resale points in Max specifically.
They can't be merged - in Max - for Embarc or Diamond. An Embarc or Diamond member that buys resale points can combine them to use within their own "collection" - for Embarc that means that all 9 resorts can be booked with resale & retail points together, regardless of how they were acquired. Diamond works the same way.
Here's the discussion for Max specifically:
Should one have bought resale points first, and then, later, retail points to get into Max they merge for Max and the original collection, of course. If another number of resale points are bought afterwards, the resale points are NOT useable in Max. You would need to again buy another batch of retail points to make them all useable together.
IOW: You can't buy 4000 retail points (to get into Max) and then afterwards buy 20,000 resale points and then use all 24,000 in Max just based on that original 4000 point purchase.
HGVC may work differently in Max but I would be surprised because they're trying to keep things "standard" across the board for that (as much as possible). It just wouldn't make sense for the developer to allow that. The same principle applied to Extraordinary Escapes and The Club before Max was introduced by Hilton.