I came up with another posssibility after first replying to this issue... - Edit 1
Before modification by Shannow at 15/12/2009 02:12:06 PM
WH (To lose the sun) - Cadsuane herself, garbed in unrelieved dark green, sat easily on a tall horse with a black man and tail, maintaining the weave that made the gateway… Nesune Bihara, all in bronze wool, rode through the gateway looking around as if trying to see everything at once, and then Elza Penfel …
That's quite large for someone of her strength. However, if angreal make gateways larger then it contradicts the whole concept of gateway size being linked to your potential, since angreal don't increase your potential, just the amount of Power you are able to hold.
I'm not sure if it really contradicts it. Two women who link can suddenly make a much bigger gateway, and yet it's still woven by only one of those two women. How does the gateway measure the combined potentials? I very much doubt it does, and that it has to do partly with creating a hive mind that allows a greater sized gateway. However, considering angreal and sa'angreal contain buffers against mental damage, they may allow larger gateways. We've never seen an example, really.
The women rode through in single file through Cadsuane's gateway. Since she didn't have to make gateways for large armies like the Ashaman in PoD or Neal and Grady, or Sammael in CoS, she probably made the gateway higher but narrower, in order to make it more convenient to ride through.
Therefore, a gateway by Cadsuane that is 8 feet by 6 feet = 48 square feet, is still smaller than Egwene's gateway of 8 feet by 8 feet = 64 square feet.