Those are really good papers &amp; I highly recommend them. A couple of things I&#x27;ve always wondered about them:<p>- their proposal seems to require either coordinated legal regimes &amp; consistent global clocks or a monopoly exchange, both of which on the surface seem impossible.<p>- their matching algorithm both still has a time priority component as well as a random or pro rata component, which is problematic.<p>- finally, the main complaint seems to be with the profitability of the arb not decreasing, but isn&#x27;t that a direct function of the legislated price floor imposed on the markets?