Was thinking about this some more. For a while I have wondered if the larger pools are running a standard stock node or something that is highly customized. And what other configurations they may have.
When you see information like this it makes you think about what they have changed on the back end and why. And if it's better for the pool / miners.
I saw this:
According to this Poolin.com and Kucoin pool have highest lost average fees per block, and we know they are not at all the biggest pools.
And then thought, there has to be a reason, but since we know more or less how core operates unless they really tweaked their config are they even running it or something else.
Thinking about what I said here:
Along with agreements with exchanges, i.e.can exchange "A" always send out at a low fee since pool 'B" will always put it in their next block since they are getting BTC on the back end.
Is the possibility of a FU to certain people. i.e. we don't like centralized exchanges so all TX from known exchange addresses will be ignored.
OR just avoiding US based ones like Coinbase / Gemini and so on or


Unless they come out and tell us we will never know, but it's an interesting thought experiment.
-Dave