if you subscribe to nba league pass this season you will be able to watch an hd feed but it would be on the rsn whose hd feed was picked up by league pass. lets say the nets are playing the heat in miami and the game is in hd. both yes and sun sports may be broadcasting in hd. but league pass picks the sun sports feed, that's what you see.
you wouldn't be able to watch that hd game live on yes. you might get to watch a replay of the game after the fact, but not the live feed. understand?