[Cincy Peach]

wouldn't the most efficient programming be to randomly select the first (players x 2) cards in the deck, and then randomly select the remaining cards if and when they are needed?

There is also a security arguement for generating the cards 'just in time', as it would be harder for a read-only hacker to exploit the system.

It seems to me that the optimal programming for CPU usage would be to never generate a card more than once, and the optimal programming for security would be to never generate a card in advance.

There might be something to the idea that the turn or river is randomly chosen when the turn or river comes. But as TC pointed out, so what? Nothing you can do with the information.