2012 RDS Gateway Farm

I don't fully understand how RDS Gateway Farms work in 2012, maybe someone can fully enlighten me here.

RDS Gateway doesn't have any inherent load balancing ability, so that needs to be done with hardware or NLA. Fine.

So the load balancer interface is lb.domain.com and the two gateways are gw1.domain.com and gw2.domain.com, the LB interface will balance the incoming connections to each GW.

Inside the GW config there is also section for farms. So you put in gw1 and gw2 in there, status is OK and your done.

1) If the GW's are already being load balanced by the hardware device, what's the point of the gateway farm configuration in gateway manager?

2) Also if 3391 is being used for better performance over UDP, how to you balance that via hardware? Obviously port 443 is being balanced between the two gateways, but do you just balance the UDP port as well? How is the load balancer going to know that the given udp and http should be balanced as a pair to the same gateway or does it not need to be?