How often you get paired board and triple barrel that gets to SD. I don't think not that often enven in those huge DB?

If one set of data is from ignition which gives all hole card info (I think?) and the other set of data is from pokerstars, which doesn't include hole cards unless the hand went to showdown, then the stars data will be biased.

When the hand goes to showdown the bettor is more likely to have a bluff as they will unblock the board. So if the stars data is filtered only for went to showdown, which would be necessary to determine the bluffiness of this spot, it will make the line look more bluffy than it really is.

Wouldn't this be the case for every river spot, not only the paired boards?

Yes. I took a training course once that was centered around MDA and the coach acknowledged this showdown bias but sort of handwaved it away and said it might only affect the bluff frequency by a few%. I was a bit skeptical. But if DooDoo's data is indeed iggy with hole cards including hands that didn't show down, and yours is stars showdown only hands, well that 3% actually looks like a pretty good estimate.

I wanted to follow up on this as it's a concept that I struggled with when getting into solver work as well, and is a common misconception people have about theory/GTO. When our theory perfect opponent bets the river, his range is optimally balanced value/bluff for that size. If we fold all of our 0EV bluff catchers all the time, then yes, the value of his bluffs go up. But the value of his value hands goes down by an equal amount. His betting range does not make any more money. He'll have a cool red line though, and we'll have a bad looking one, but our green lines won't budge.

The only way we lose more money by folding a higher % than the solver recommends with 0EV hands is if our opponent adjusts to our over-folding, but he in doing so opens himself up to exploitation and thus the levelling war begins again. That's why some of this MDA data can be helpful in these spots, especially in anonymous pools where we don't get player specific reads. We can do better than GTO by shifting our play with our 0EV hands, either by folding in under-bluffed spots or calling in over-bluffed ones.

obviously if opponent exploits our folding to much we can re-exploit them. If you dont think you're opponent will counter adjust then just do whatever is the most +ev The reason i say it matters what you do with 0ev hands is it opens up a whole new meta game.

I'm 1/1 more please; as someone that plays only untracked it's interesting to see if my intuitions are correct

I think people under bluff paired flops going to the river. Interestingly, I think they are correct to do so, because people call too much in the bluff catching position. You can exploit the pool, by being reluctant to bluff on the river and also by not calling down as much. I don't have access to MDA so it is only just my observations which may or may not be correct.

I did enjoy the poll. I think it would be fun/productive to see more of these posts in the future.