That post made some incorrect observations. Star Platinum getting him a smoke doesn't mean anything. D'Arby wasn't even looking at him when he put it in his mouth. A normal sleight-of-hand practitioner could put a cigarette in his mouth without D'Arby noticing him in that circumstance, to say nothing of a Stand like Star Platinum. And getting him a drink isn't outside of Star Platinum's established capabilities, either. It was bringing him stuff while he was in his jail cell, back when he didn't even know what was doing it. There's no way it was pulling in things like a computer and an electric guitar while staying within two meters of him.Now check out Jotaro's profile in chapter 16. He's not aware of his own poker face!
Also, I highly recommend this post for reading, it provides a nice observation of this game, but with spoilers for the end of Part 3:
JJBA Theory: Jotaro Doesn’t Actually Know Anything About Poker