[wrsh07]

This is just noting that different brokers give different performance

That doesn't really have anything to do with pfof (TD Ameritrade gives better execution and receives pfof)

https://news.ycombinator.com/item?id=42378516

[loeg]

Presumably a market maker would pay (PFOF) slightly more to deliver slightly worse execution (keeping the spread).

[wrsh07]

Sure that sounds plausible but it's literally not what happens in practice (see the other comment I linked that discusses research on this very thing)

[loeg]

Yeah, I've seen the Levine column on it.