[Spicymoose]

Basically your plan here is to call any diamond, 7, or 4 on the river. But there are only 14 of these cards (or slightly less, considering some diamonds could be taken), meaning you are only calling 25% of all rivers. You are trying to win 5 BB (3 BB pot, and SBs turn and river bets). If you were always good on the river, you would still only win 5 BB 25% of the time, and lose 1 BB 75% of the time. But, considering you are only good on the river sometimes, this plan doesnt work. If we say you are good on the river 50% of the time when you hit, then that means that you lose 2 BB 50% of the times you hit, and win 5 BB 50% of the time. This is a net of 3.5 BB when you do hit.

So, now 75% of the time we pay 1 BB, and 25% of the time we net 3.5 BB, which is a slightly EV+ situation.

This means that if we are good on the river 50% when we hit, your plan is good. If you don't think we are good on the river 50% of the time when we hit, your plan isn't good.