3: you do not choose what coins you mine. you only receive workunits for that algo. The coin selection is strictly for what you wish to be payed in; which BTC is highly recommended.
Can you clarify please? As I read D3 miners were not able to mine any other X11 coins, except Dash, because Dash was fixed in it's hardware.
You are saying that zpool choose the most profitable coin, but how zpool can iflluece D3's predestination for mining only Dash?
D3's can mine any X11 coin which we currently have 60 of them on the pool. It mines what it feels it can get the best profitability from. They're not just for DASH.