Mwan3 with same gateway


I am trying to setup multiwan in my WR1043ND v2 and is not working properly. Searching a bit, i fount some information that 2 interfaces with the same gateway generate a lot of problems, does anybody know about it?

My situation is that i have 2 links, with ips in the same network and same gw. Is bonding a option? Because i don't really need load balance 2 ips, i just wanna have more speed, because the switch only have 100Mb ports.

Thanks a lot,