Jim,
I read what you wrote in the upgrade guide. There is no mention in what you wrote WHY one would want to add the tunable to their firewall configuration. What specific symptoms would lead you to needing this tunable?
With respect to the open mesh access points, the traffic doesn't need to be handled by the firewall at all. The main issue was messages filling up the system log, making it basically unusable. Windows NLB is another animal altogether.
Also, my question of the security ramifications of adding this tunable, thereby reverting the kernel back to its previous behavior, has yet to be answered. Just for the sake of completeness, I think we should have a discussion of how this impacts security. Was the behavior changed from FreeBSD 8 to FreeBSD 10 just for the sake of being RFC 1812 compliant, or is there a good sense security reason for the change?
Is there a possibility that logging this kernel message could be suppressed (in a future version of pfSense), instead of enabling a behavior that violates the RFC?
Thanks for all you guys do,
Anthony