Quick thought on how to make blockchain-based fee estimates work better
in the context of out-of-band mining contracts: have miners advertise in
their coinbase's what fees were actually paid, as opposed to appear to
have been paid.
This is interesting, but I suppose some miners may have business models that can't be easily summed up as a "fee" - like all-you-can-eat deals with certain providers, or preference to certain kinds of transactions etc.
For the concern that estimation might force fees down too far if miners include private transactions, I thought the estimates were calculated only on broadcast transactions, so transactions that just appear in a block won't ever influence the estimate?