When does Nut Flush Blocker apply?

[whiskyjohn]

Hello,

I understand the concept of Nut Flush Blocker (NFB) but I'm not sure when it applies.

For example, I am running Notetracker to look for certain weak draws and I found the following hand
with the following board:

PlayerA: KdJc
PlayerB: KcTd
Board: 9dAd8h5d7c

Is the Kd ever a NFB on any street?

If I go into the filters and select "Nut Flush Blocker Any Street" this hand is getting flagged.
However, when I select for the NFB on individual streets (flop/turn/river) none of them flag
this hand. Furthermore, if I make a filter like (NFB On Flop) OR (NFB On Turn) OR (NFB on River)
it also doesn't flag.

What's going on???

John

[kraada]

That should flag as the nut flush blocker -- the Kd is the card that, if you had it in your flush, would make the best possible flush, so it is the nut flush blocker.

I'll make a note to look into the individual street versions, they should be working.

[whiskyjohn]

That should flag as the nut flush blocker -- the Kd is the card that, if you had it in your flush, would make the best possible flush, so it is the nut flush blocker.

I'll make a note to look into the individual street versions, they should be working.

Please take a look. In the example above, when should the Kd be counted as a NFB?

On the flop, there are only flush draw possibilities with both Players. If I test for NFB here, nothing is flagged.
On the turn, the 5d gives a made flush to any player with two diamonds, which is not the case here. However,
the Kd would be a NFB to such a hand. However, when I test for NFB on turn, again nothing is flagged.
On the river, the 7c doesn't change anything. When I test, nothing is flagged.

But as I said, if I test for NFB Any Street, then the hand is flagged! When was the Kd (magically)considered a NFB?

Also, to change this example slightly, what would happen on this board:

PlayerA: KdJc
PlayerB: KcTd
Board: 9dAdAc8c5d

On the flop, the Kd is a NFB only to a turn OR river diamond. The Kc is only a NFB to a backdoor club AND diamond.
On the turn, the Kd is a NFB only to a river diamond. The Kc is only a NFB to a river club.
On the river, the Kd is a NFB to any opponent with two diamonds.

Which of these get flagged as NFBs?

Thanks for any clarifications,
John

[kraada]

This is very strange because there is a flag in the database for the nut flush blocker and the "Any Street" flag is literally just testing whether the flop is true or the turn is true or the river is true. So that's one piece of confusion here. If you could please submit this hand to our support team here so that we could look into what's special about this hand, that would be good.

The flag should be true for the turn and river in the first hand you've pasted. You can't have the blocker until someone could have a flush. The blocker in your second example is the Kd and only on the river.

Think about it like this: when there's a possible flush, if you hold the nut flush blocker, you can be certain the other player doesn't have the nut flush. He can have any other flush, but not that one, so you know he can't have the best possible flush and he knows he doesn't have the best possible flush. It's only about actual flushes that someone could have, not about draws to flushes someone could have.

[whiskyjohn]

This is very strange because there is a flag in the database for the nut flush blocker and the "Any Street" flag is literally just testing whether the flop is true or the turn is true or the river is true. So that's one piece of confusion here. If you could please submit this hand to our support team here so that we could look into what's special about this hand, that would be good.

The flag should be true for the turn and river in the first hand you've pasted. You can't have the blocker until someone could have a flush. The blocker in your second example is the Kd and only on the river.

Think about it like this: when there's a possible flush, if you hold the nut flush blocker, you can be certain the other player doesn't have the nut flush. He can have any other flush, but not that one, so you know he can't have the best possible flush and he knows he doesn't have the best possible flush. It's only about actual flushes that someone could have, not about draws to flushes someone could have.

Ok I have submitted than hand in question to your support team. Hopefully you can recreate the problem.

I suspected NFBs apply only to actual flushes someone could have and not draws to flushes. I just wanted to make sure. Therefore, as I now
understand it, there can only be one possible NFB per hand, as there can only be one possible made flush per hand. Correct?

Thanks.
John

[kraada]

That's my understanding, yes.