I was keying off of this "The BIG TCP patch set adds the logic necessary to generate and accept jumbo packets when the maximum transmission unit (MTU) of a connection is set sufficiently high.", which made it sound to me like the author believed that the MTU was 185k
> Modern network interfaces perform segmentation offloading, meaning that much of the work of creating individual packets is done within the interface itself. Making segmentation offloading work with jumbo packets tends to involve a small number of tweaks; a few drivers are updated in the patch set.