But Rand is the most powerful channeler in the world. How can you use him as a standard for gateways in battle? Most channelers can't even Travel.



And what good would this do? What does it help for Rand to hold a gateway open for five seconds? He could let a bunch of men through, all of whom would instantly be met by enemy soldiers, shadowspawn or channelers. Even Rand's biggest gateway has serious limitations for reinforcements. RJ's own answer implied that circles have limits too when helping their armies.



Why would there be a single defender? It's much more chaotic than you portray. There could be 500 channelers on both sides, each trying to weave gateways to a location to send more troops. As the gateway opens you have rival channelers sending destructive weaves through the opening, and other enemies trying to unravel your gateway or block it. Then you have your people trying to prevent all of this. It's mayhem. It's not unlikely that a man like Rand could open six gateways and hold them open, with five being decoys and only one being used. It's a whole different war game when it comes to channeling. RJ also said that one could use multiple gateways but the size would limit how many men you could push through per second.



Probably.



Why? What happens if there are hundreds of channelers like one would expect in the War of Power? Besides, most of it is trying to stop reinforcements from coming through those gateways, not actually stopping the spinning. There are only three known channelers who can do that, and I doubt they were present at every battle.



Even a simple warding can take days to unravel, according to Moghedien. Even if Demandred could do such a thing, he doesn't have the strength necessary to make a substantial difference. Rand needed an angreal to ward the Aiel encampment. So if Demandred could also ward a mile in every direction, it would not help him if Lews Therin could make gateways just outside that area.



I think the battle has to do with forming many gateways, holding them, blocking them, preventing blocking, and destroying reinforcements. You could have people countering each other's weaves on both sides until you have a dozen people countering each other's counterattacks. It would be a messy thing.